Of the two Ricks:
The '83 should sell pretty low, as there's not a lot left that's original, it will take a few hundred to bring back to spec if that's what you're interested in, or just play it as is.
The bridge is an improvement in set up terms compared to the original, and since it's already modded, you may as well leave it.
The pickups possibly don't give the bass the Rick tone, but may sound decent.
It depends on what you like.
Personally, I'd change the pickups (also it would need a new partial pickguard) to RIC stock units ($225.00 http://boutique.rickenbacker.com/Pickups_c_12.html
The '92 may go for a decent price and should be a good player. Nice used bass.
Sorry, I have no experience with Vox instruments however.