Just to let you know, all Warwick MEC pickups with the MEC written in gold are active pickups, and require a battery, even if bypassing the active preamp, which is in the majority of their basses.
The Rockbass line, which is definitely well worth the money, has the most fully passive offerings:
- Streamer Standard
- Corvette Passive
- Corvette $$
Also, the Streamer LX has passive pickups, but a non-bypassable active preamp... But it wouldn't cost a lot to rip it out and wire in a few pots and stuff.
However, I find the silver MEC's (their passive ones) to be the noisiest single coils I've ever heard.... They sound great, but the single coil hum is a bit ridiculous IMO, and I've owned the Rockbass Streamer LX, and the fully passive version of the Corvette.
Other than that, yeah look for a used Warwick... Though it does sounds like a Jazz may be better for you.