You can get an AR 10 in 358 win and there are plenty of cans available that will work with it.
The hole in the can does not have to be 35 cal, witness the GEMTECH ONE which works with everything up to 300 winmag. A 458 SOCOM can would work fine with the 35 Rem. So buy your mauser, get a Brownells bbl in 35 Rem, get it threaded, put on the can and report back.
You can always load a 358 down, change the buffer and get an adjustable gas port if you want 35 rem performance.
You can't load a 35 Rem up !