I've a Dimarzio X2N-7 in a bass and it sounds mighty. Some kind of Jackson stock humbucker in another which is quite good. And I have a SSH Strat I rigged up as a super short scale bass, and kept the stock pickups, with no issues.
That said, if you want a bass pickup in guitar humbucker size, there are a few options, EMG make both active and passive, Rio Grande make some called Pitbulls(I have one, it's pretty sweet), or you can find NOS Gibson bass pickups from their old Les Paul basses on eBay from time to time. I got a pair of them once, incredible sounding pickups.