Augy, I don't think I've ever seen one like it? Not that it would make a difference, or not that I'm any kind of expert... But you should be able to get one of the repro units at a resonable price and replace the whole thing?

I don't know that you'd have much luck in finding parts to fix the one you have, as it seems to be period correct, but maybe not stock equipment?

I'd go with a repro?

Brett - 67 Drop Top 455!