That is unusual!
I like it.
One can make 10.75X68 out of 458Lott brass (and I suppose 7mmRM, 375H&H or other belted magnums) but it's a lot of work - turning off the belt and resizing the base to do it properly. Just not worth the effort IMO as once you have ten or twenty pieces of correct brass that is enough unless you are really dead set on using it quite a bit.
Also, Hawk makes bullets but you can also use the 400gr 404 bullets. A bit heavy depending on what your magazine can take in the OAL department.
I make my bullets from 40S&W brass and that works well for the limited use my 10.75 gets. Quite gratifying though...
As to the back and forth about the 404, it is correct that the only thing the 404 and the X68 have in common is the bullet diameter (by .001-.002") and that the rifling twist for both in the original Mauser barrels was the same eventhough they have differing bullet weights.
The 404 was indeed designed to fit in a standard length Mauser '98 as Rigby had an exclusive on the Magnum Mauser actions at the time of it's introduction.
Funny, though, if Jeffery had trimmed the case neck to one bullet diameter in length it would have been an easier fit (rail work not withstanding). Instead, the 404 sort of mimicked the 450-400 3" Jeffery in design with a longer then necessary neck - at least as we look at it today.
The 11.2X72 Schuler is an entirely different case as well which ironically suffers from a too short case neck and an odd bullet diameter. Very powerful round though.