You have an early Sovieticon sks 45. The 45 degree angle forward gas port and the cutout are on the bolt (where the bolt serial # is located) indicate that your rifle was made in 1950 or 1951. The bolt design also means that you have a spring loaded firing pin, which was phased out and replaced with free floating firing pin some time in 1951. Your rifle will also have a milled step on the receiver fore-end and an early style rear sight block. It would be lovely to see it in an original soviet stock.

Are all the serial numbers matching?