I put a set of EMG Geezer Butler PJ pickups in my Frankenjazz. They are a passive set with alnico magnets (unusual for EMG). I don't know what they did to make the bridge pickup quiet, but it is. It's also hotter than a standard Jazz pickup to balance with the P pup in the neck position. I think they sound killer.

Of course, I should note that I am not really a jazz bass guy. I pretty much never solo the bridge pickup. I tend to use the bridge pickup as an a kind of tone control. Up when I want a bit more sass or honk. Down or off when I want P bass sounds. Usually down more than up.