I can send you a new Amphenol 82-63-RFX. Although made for RG-8, 213, etc., the poop sheet shows it will work with 216 which is 75 ohm. If you want to try replacing the entire connector or just see it the center conductor will work, send me an address and I will stuff it in an envelope and toss it at the pony express lady when she goes bobbin by.
is that connector 75ohm? from my memory 75ohm connector wont mate well with the 50ohm. (from my memory the N female pin is bigger on the 75ohm vs 50ohm.)