Welcome to the forum. The rifle looks like a great shooter that would bring more enjoyment than most $500 to $600 purchases these days. The metal that can be seen appears to have a good finish though the bolt is in the white (popular, but not period correct for the collector guys). Correct milled trigger guard that appears to have a slight flat spot on the bottom. Won't affect function and very common. (also fixable if you desire). Presuming a previous civilian owner didn't shoot it a ton, the barrel could be quite good. As you noted, the serial number is just on the safe side of the heat treat change.