Thanks for the replies. ;D

That is much like one of the parts I got, but it is the one that is too wide. Spring that works is like that, only 2 winds between the ends, which are at a wider angle, but must be compressed to a fairly sharp V to get installed. I had an idea after posting this last night, and I'm headed for a local hobby shop to get some small tubing today.

I don't know for sure when my dad got this. Had it when I was a teenager for sure. Mid '60s?

S/N is just 11611, no letter.

Thanks again. If my idea works, I'll post a pic or 2. Rarely have I been this frustrated working on a gun, but maybe it can finally be finished. 8)