The foam surround on the Spica woofer is known to rot (perhaps the cause of your buzzing), and I don't believe that exact woofer is still available. A replacement woofer would most likely require a change in the speakers x/o. Collectors of vintage speakers for that reason buy extra examples, just to have spare parts, as do restorers of vintage automobiles. I restore vintage drums, and buy damaged drums just for the parts.
Setting a price for Spica TC50s
I have a pair of Spica TC50s, that are cosmetically in fair shape, a couple of nipped corners, etc.. One of the speakers has a slight buzz in the mid-range woofer. Nothing loud, but annoying. My question is, should I be content getting less than $100.00 fir these? Is there any real market fir them?