first thing is...are you looking to get rid of hum, or do even have any? Or even care?
secondly..are you only looking for a beefier J sound, or do you need more low end cut-through?
9CBJS (true single coil)
9J#1 (split coil)
9CBJD1 (dual coil)
On the Bartolini web site, the 9CBJD1 are suggested at $25 more a set than the 9CBJS, but at Best Bass Gear they are the same price and much lower than the suggested.
Best thing to do is shoot an email to Brian at bestbassgear and tell him you want Barts but explain what you are looking for - he is the expert. For me, the playability and feel of the geddy jazz was more important than reserving the vintage jazz sound - I wanted a jazz/precision mix sound with emphasis on low end clarity to cut through the band. I put in 9CBJD1 set and if I lower the bridge pup, the P sound comes through like thunder. If I set them equal, the J sound rounds it back out. They are not as 'growly' as the factory pups, but I knew that based on my needs. I also put 500K pots in to help offset the less brightness - works well.
http://www.bestbassgear.com/bartolin...j-pickups.htm#