I assume there is a K prefix to this serial number - somewhere to the
left of it on the butt . That is a part of the serial number. Does this
full serial number appear on the rear face of the cylinder, and on the
flat area under the barrel ?

This V7 mark - where is it on the gun ?

Assuming the serial number is K54xxx, this is a 1949-ish gun. Its a
K-22. This is way before model numbers.

Mike Priwer