There's a world of difference between a canned hunt and a plains game hunt on a fenced South african game farm.
The former is where an animal such as a lion is captive bred, spends it's life in a pen and is then (usually) transported to a different area that he (or she) doesn't know at all, has no idea of escape routes and terrain etc and is then executed (it's not hunting) a few hours or days later..... often whilst still under the influence of sedating drugs.
The latter is where plains game animals spend their life on what is usually a big to huge area with a fence around the outside. They pretty much always know the terrain, the escape routes and predator dangers etc.
As to are there any properly free range areas in RSA where eland can be hunted?........ very few is probably the best answer you could get but one of the guys that could probably find such an area for you is Jaco Human at
Index.
Your other option is to look outside SA and find a true wilderness area but that of course is going to put your prices up dramatically.
If you want to go halfway between the two, you could opt for somewhere like Tuli Block Botswana where there are game fences but are usually what might be termed porous and is usually a wilder option than that of RSA but not as wild as a true wilderness area.
You also have to bear in mind that despite it's size, an eland can jump like you wouldn't believe and can clear most game fences without any problems at all. - I've often seen them walk up to a 2 metre high fence, settle back on their haunches like a dog and then just sail over without any hassle.
In other words, even in a fenced game farm, an eland can easily be a free range eland if it wants to be.