To answer OP: I've lived in AK for almost 30 years, 5 of those in the Alaska Bush. I also practice law in Alaska and I've represented more than a few people charged with fish and game violations for a wide variety of offenses, so I have a pretty decent idea of what is a DLP (defense of life and property) shooting is. Finally, I live about 5 minutes down the road from Sutton and have for more than a decade.
Based on all of that, I would say that they should get a firearm but with the proviso that they are going to practice. There's a free range out off Maude roade that is about 15 minutes from their house. To be responsible gun owners, they need to practice. They don't need a concealed carry permit legally but the training from those courses is really valuable. I've taught the legal portion of CCW courses for several years and I would heartily recommend a newbie gun owner go through the course even if they don't obtain a CCW.
With that said, a newbie gun owner is going to want a firearm with the following characteristics: 1) reliable; 2) sufficient impact to deter large wildlife such a bears and moose*; 3) easy to operate; 4) easy to carry; and 5) have ammo that is readily available and comparatively inexpensive. No single factor will dominate and economists are fond of saying "There are no solutions, only tradeoffs." Yes, a .470NE will do more to stop a bear than a .223. But which is likely to be shot more? Which is easier to carry? How easy is it to get ammo for the .470 v. the .223? This doesn't mean that I recommend the .223 but you get my point. A .460 that never used because of the recoil or cost of shells does no good.
Given all of those factors, I would recommend a Glock 20. Glocks are like Toyotas: they just run and they are infinitely customizable. Recoil can be a bit stout but its manageable, in roughly .357 territory. 10mm ammo is much cheaper than .460 and the gun is far easier to be carried that a really large pistol or a shotgun, which means it is far more likely to be carried than a large pistol or shotgun. A Kenai chest holster from Gun Fighters Inc. can't be beat. It goes on over most clothes; its kydex so its not affected by weather; firearms 'click' into place and do not come out unless actively pulled out. While I haven't submerged mine, I wear my Kenai chest holster while I'm fishing and I've stumbled a time or two on slippery rocks. Gun doesn't even budge. And its extremely accessible. Also, a Glock 20 is pretty reasonably priced, far more reasonably priced than most other options. (I have used a different 10mm for years and just got an FM510 and want to see how that does but that's just me.)
As far as shots 50-100 yards away, when it's your home and you're dealing with a DLP situation - don't. Just don't, at least in these circumstances.** First off, at 50-100 yards away, the animal is not likely to seriously damage your home, particularly if you're 'bear aware' in terms of how you get rid of your garbage. DLP generally means that you are facing an 'imminent' threat to life or limb and that is way too far. Alaska juries deal with these animals all the time and they will be less than impressed by your sudden need to protect your life from a bear that's 100 yards away. One nice thing about a firearm is that loud noises can scare bears away. Unlike bear spray, you still have rounds left and can defend yourself. Dealing with animals is about the only time I would recommend firing a warning shot but then only when the muzzle is pointed in a safe direction, like, into the ground or the river (if you're fishing). Moose eating prize apple trees is likewise not really sufficient to justify killing the moose. Most locals view that as the cost of doing business. Don't want moose eating your trees? Put fences or other moose deterrent around them. Any local nursery will know how to do this.
One nice thing about the 10mm - if they have to deal with 2 legged intruders, you know the cartridge will penetrate the many layers those intruders may well have on because of the Alaska winter. I don't have a lot of confidence in the 9mm having much ooomph after going through a parka, Arctic Carhartt bibs, a thick flannel shirt and other layers of fleece before reaching vitals. If you ever have to fire on a 2 legged intruder: 1) aim for center mass; 2) fire until the intruder goes down then stop; 3) call 9-1-1 and say that there is an introducer WITHOUT SAYING MORE; 4) when the cops get there, say that guy was on yoru property and you believed he was going to seriously injure or kill you and you shot to stop him and then say, and I quote, "NOW I WANT TO TALK TO MY LAWYER. DO NOT TALK TO ME ANYMORE WITHOUT MY LAWYER." Then contact a lawyer from USCCA or Armed Citizens' Legal Defense Network or LawShield or a similar organization and SHUT UP. If I emphasize keeping your mouth shut, its because I've never seen someone talk themselves out of trouble but I have seen lots of people talk themselves into trouble.
Again, this is my 2¢. Your mileage may vary. I've found when it comes to guns and protection and bears and self defense, the discussions involve a lot more heat than light. Just remember that opinions are like assholes - everybody has one and they usually stink.
*Sutton is one place where brown and black bear populations converge. Frankly, I would be more concerned about black bears than brown bears most of the time because brownies don't consider humans food. If you leave brownies alone, they generally leave you alone. Same can't be said for black bears. I say this as someone who's chased brown bears out of my yard and my boat and made sure they didn't come into my camp.
** we have chickens and there's a fox that sometimes steals my chickens. That fox is about 75 yards away and I want to eradicate the fox but so far it's been pretty elusive. I also have a pretty good setup - AR 15 in .300HAMR w/ red dot sight and a suppressor to not disturb the (few) neighbors. That setup, though, is not very newbie friendly, nor is it particularly pocket book friendly when compared to the Glock 20.