If I had that rifle (which I sure would like to have if you ever decide to sell it) I would most DEFINITELY rebuild it. As a general rule, only the British made them into .308 usually to get it to conform to their caliber.
It was made between December of 1941 and August of 1942. The re-barrel is as it shows, December of 1950 and the rifle is what we call a "mixmaster" of various parts, like the Springfield barrel and bolt. An obvious arsenal rebuild.
Mark
