HCD, I concur with the others -- that's a K-38 Masterpiece from 1952 wearing target stocks that weren't manufactured until a few years later, probably late '50s/early '60s. Under any circumstances they are not later than 1968, because that's when the diamonds went away. The gun looks to be in pretty good shape. The target stocks are an upgrade and add value to the gun. If I am reading the condition of the finish correctly (95+%), in California that would be about a $600 package.
Target stocks did not usually have serial numbers marked on them, but the original magna stocks on guns of this period did. If you wanted to get some age-appropriate stocks for the gun, look for diamond magnas with a stamped number near your serial number. Anything within 20,000 would probably be OK.
Here's a countertop snapshot of a K-38 with standard stocks for this model:
This gun is K100091, the slightly older brother of yours. It was shipped in December 1950.