hmm; allparts has the nice bourns 500k push-pull
audio, but the less-nice (but still OK) alpha
linear push-pulls.
what's the plan for the push-pulls? if you're just gonna switch the pickups to individually parallel, i wouldn't bother; you lose power and lows, but don't really gain much of anything in trade (just like switching a stock P-bass to parallel is usually disappointing).
parallel would come in handy if you were gonna wire the pair in series
with each other, to keep things from getting too dark and boomy.