I used to own a Low End Jazz 6-string. You didn't mention the width of your routs, but the LEJ had extremely narrow ones (21mm), so the only pickups I could find that fit without routing were Delano narrow soapbars, as seen on this page:
http://www.bestbassgear.com/delano-6...ng-pickups.htm
I'd describe them as neutral sounding, not hyped, with medium output. I wouldn't say they sounded totally authentic compared to a real Jazz Bass, but close.
I also talked to Carey Nordstrand, who said he could make me some custom Big Singles to fit, though they would have to be raw (no covers).