Measure the tuner diameter. Chances are, a typical Gotoh-style tuner (1/2" diameter) will fit it perfectly.
I can't think of any bridges off-hand that use the 4-screw set like that. But if you're willing to drill your own holes, you can never go wrong with a nice black Hipshot A bridge.
String trees are easy enough to find. BassPartsResource, etc sell them. I have a black one on my Frankenjazz, and it looks schecksy.
No-pole replacement pickup covers would look sweet too.
Pickguards are tough to match. But if you make a nice trace of it and send it to WD Music, they can check and see if they have the template available and get you a solid black pickguard replacement.
Along with the pot & cap upgrade (presuming they are in poor condition), any bass benefits from a nice copper shielding job.
LaBella tapes are lame. Go with some DR Black Beauties. Same black color, superior tone. (

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