That SN would put the shipping date in late 1941, probably some time between September and November. It would be a pre-Victory. At that time it might have had the so-called Brush Blue or Bead Blast Blue "Black Magic" oxide finish, but it could also be the pre-war Carbonia bright blue finish, as things were in transition in late 1941. It's generally accepted that the changeover from Carbonia to Black Magic happened at around SN 860000. In early to mid-1942, the finish was changed to a dull phosphate, like Parkerizing. It's a little surprising that the smooth grips seem original. The changeover from checkered wood grips to smooth wood grips is usually given as January 1942. But anything is possible. A nice un-messed-with pre-Victory example from that period is good to find.