i've got the 4 string,, also had the 5 string but let it go,, as you can see, i've modded it a bit..
first off, i changed the tuners, as the stock tuners felt really cheap,, & if you want pickups,, Nordstrand is the only way to go, imo of course. mine is a set of Fat Stacks with coil tap.
Carey makes 5string pickups also, that may not be an exact fit in your bass, there may be a sleight gap around the pickup, or for an upcharge, i think he also makes custom sizes, check his website.