Hi John,
looks like a very playable EB3 - they were not available fretless (perhaps as a special order in the seventies, but I've never seen one that was stock) so might attract attention from somebody wanting a real fat fretless sound.
It has had a fair bit of work done to it though. You are right - late 1971 - have a look at the pot codes, I would expect them to have the code 1377142 (meaning the pots were made in week 42 of 1971). They might not be, but all of the very latest slotted headstock EB3s I have inspected have a similar serial number (beginning 6) and those pots.
It has been stripped down and refinished, and the gold parts added at a later date I'm afraid. The gold around the bridge is most likely to correct a tilt and/or too high action. This is a bit of a drastic solution, but in the days before the net, was probably seen as the only option. [in fact a tilting two point bridge can often be repaired by making sure the grub screws attaching the bridge to the post are in good order].
As for selling, it will probably be a bit too much work for a cost-effective restoration, so is probably best sold as a great player. Desireable bass, whatever the condition. Parts alone should bring in $500
Jules