Is it worth it?
I've never heard of one. It may have been marketed in Europe but not the U.S. Is it worth dumping some brass into? Or, is it an experiment. You could scour the countryside looking for an exact replacment for the machine head or but a matched set or just pick up something that fits or a set that fits.
Try surfing for instrument part catalogs online and see what's out there.
On the other hand... strip it down, refinish the instrument, refurbish the electronics, clean it up really nice and there you go, a bass to call your own.
That's my 2cents or tuppence or whatever you call money in the UK.
The Bass is the butter on the bottom of the pan!