"Knob Questions!"
See 'em on TB nearly every day! *rim shot*
Seriously though. If your bass' pots have a solid shaft then any after-market Fender-style knobs which have set-screws should fit.
If your bass has split-shaft pots then push-on knobs (eg those used on a Strat) might be the way to go. Although set-screw type knobs may fit as well.