If you still want it looked at by a gunsmith who is very knowledgeable about a Parker, I can vouch for Bill Schwartz, Ellijay Ga. (706) 276-7668. He fixed up a CH 12 that I have.

That is a very nice original gun.
The only thing I would add, is DO NOT let anyone go near that gun with a screwdriver, unless they have some credentials as a double gun smith.

I took the gun to Jim Kelly in Darlington, SC, a gunsmith recommended by several members here for service and cleaning. Although his shop seemed very busy, Jim spent some time with me. He and his people were very friendly and seemed knowledgeable. I look forward to hearing what he has to say about the gun other than condition, which he described as excellent. Thanks again to everyone here for helpful comments.