K4987xx = 1962

K7149xx = 1966

These are manufacture dates (when the serial number was issued). Both guns could have shipped the following year, as Engine49guy suggested.

The Combat Masterpiece is probably a Model 15-2. The Combat Magnum would be a 19-2, as stated.

As an aside, both the Model 15 Combat Masterpiece and the Model 19 Combat Magnum came standard with target sights. Standard configuration for the Model 19 was Target stocks; the Model 15 shipped with either Magna or Target stocks.

__________________
Jack
SWCA #2475, SWHF #318