You might want to look at this thread, because you've basically got the same issue - Nordstrand MM4.4 in sweet spot, Big Split in neck position?
Your P pickup is hum-cancelling all by itself, so you're going to want a J pickup that is hum-cancelling as well.
Split-coil designs like Nordstrands NJ4SE and NJ4SV, or any of DiMarzios hum-cancelling J's will get you closest to a true single-coil J sound. Lots of other split coil designs out there, too.
Stacked humbuckers are noticeably less bright, but that's not necessarily a bad thing, especially for a bridge position pickup. Seymour Duncan has a couple of different stacked jazz pickups. Their "Hot Stack" might be a good match for you, since P pickups tend to overpower most J pickups.