If you look, you can find pre64 bolts. The headspace may or may not be an issue. Of course it could be a simple as finding a bolt and having it either re-chambered to a 300 mag of some sort, or maybe having it re-bored to something like 338-06, 35 or 375 Whelen or 9.3x62. That could possibly solve a headspace issue PLUS give you a gun new cartridge to play with. Or just buy a new bolt and barrel.
