The shape of the hammer on your K22 Masterpiece suggests the gun was made before 1957 so it will likely not have a model number stamped on it.

The stocks are not correct period, being of post-1982 manufacture (but they are very pretty).

My condolences on your father in law's passing. You must have been a favorite son in law for him to want you to have what surely must have been one of his most prized handguns. The K22 is a classic in every sense of the word.

The serial will indeed have a K prefix.

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