We have investigated the John Wayne ejector hammer gun before. As I recall, it was a modern ejector gun that he was holding when the shells were ejected.

I thought once about making a Parker hammer gun into an ejector gun. It is possible to do, but making it a selective ejector gun is more difficult. If not impossible. That meaning only ejecting when the shell is actually fired. Making one eject every time the gun is opened is not as much of a problem.

Your gun 4639, was made shortly after my 20 ga lifter 4634 Gary