The neck pickup in this bass:
is an SGD Sidewinder
. It's in Bartolini's BC5 size which is the same as Bartolini P2 and very close to Bartolini MK1 (just two millimeters shorter than the MK1).
This is a very clear sounding single coil pickup but it totally hum free because of how the pickup is made. This would be a great replacement on any bass that uses MK1 pups if you want that single-coil sound.
I only have one for sale so if your bass is a one pup bass you're set! If you have two pups and want to replace both you could buy this one from me and put an order in for another one from SGD and have a $220 set of pups for $180.
$70 shipped, CONUS.