It could be rebarreled for pretty much anything with the same, .308-based case, like the .22 Cheetah (wildcat), .260 Rem, .25 Souper (wildcat), 7mm-08, .338 Federal, .358 Win, etc - until your money runs out. It could be simply rebored, for those calibers larger than .308, using the issue barrel.
I wouldn't rechamber a .308 BLR for any larger, .30 cal cartridge, because of the hassle of different bolt face size(a biggie), magazine feed , etc. YMMV.