Finding 66' pickups will be difficult and very expensive. Worse, the one you find for sale are mostly dogs. Great pickups stay in their original instruments for value and tone. Then there is the question of authenticity.... Also variability with hand wound pickups they can be all over the map.
I have tested most current vintage style pickups and I would recommend you try a Lollar, Lollar Overwound or Aguilar AG 4P-60. If the bass lacks in bass frequencies the AG 4P-60 hot is also fantastic. Which one will be the best? There is no real way to find out other than testing the actual pickups in the bass. Expensive, yes but compared to a 66 original pickup that will feel inexpensive and you can always resell the ones that did not work out.
Congratulations on the bass. I love 66P, I have played a few and were my favorite 60's basses. There were a lot made that year but despite the pre and post CBS dilemma the ones I had the opportunity to play were just great.