The EB3 had a smaller pickup in the bridge position. I think it was a humbucker, right?
Yes, the bridge pickup is also a humbucker. I think it's the same size as "mini-humbuckers" on guitars, but with four polepieces. A GFS Minitron (minihumbucker, they cost around 35 bucks) would probably do well. The fact it has six visible polepieces doesn't mean it'll work any worse underneath four strings. TV Jones replacement pickups would work perfect, but the price is as high as that of Darkstars and clones, so sadly they're not an option.
Edit: There have been people with other ideas that supposedly worked well, e.g.:
Obviously not a humbucker in the bridge position, but I've heard it works well. Again, SCPBs can be bought cheap, although Artec and GuitarFetish do not stock them, so I have no idea who else does.