The "C" prefix guns and previous do not have the same spring loaded ejector as seen on your later model. They simply had a small rod that protruded into the receiver and caught on the rim of the shell to kick the shell out. On these the mechanism had to be operated vigorously or the shells could get caught in the action.

This was later revised to include the small "L" shaped spring on the later models as seen in your last two photos, which provides a bit of spring kick to get the shell out if the mechanism is moved slowly.

I don't think you can convert the early gun to the later pattern without drilling and tapping the receiver.