I'm thinking Model 17
The ejector rod looks more like Model 17 than a post war K 22 Masterpiece.
My K22 Masterpiece is 1947 shipment per LOA, s/n 905 with matching numbers all around, plus numbered to the gun diamond grips. Notice the ejector rod and knob.
My Model 17-3 is a 1971 shipment and numbers match.
The OP's gun has diamond grips so IF original then obviously pre 1968, but Model numbers started in 1957/58.
A photo of yoke with cylinder swung out and of the butt will settle the matter.