A while back I set out to retool a vintage Strat with original pickups. Browsing EBAY is one way to find those rare parts, and though pricey, the availability seems to be there. Just keep in mind there are a lot of jokers out there, claiming this and that, and often not even knowing the originality of the item. Your best bet is to stick to reputable vintage parts dealers, like Tradeitinmusic or thepartsdrawer.
I paid big bucks for this pickup, purported 1962 Fender. It came "packed" in a baggie, rolling around in a box for miles and miles. packing peanuts? bubble pack? foam? no, this was "cushioned" with a wad of paper!
of course, the pickup arrived all jacked up, wires broken, indented, etc.
and to top it off, it was a fake/look how clean it is!!! it's the wrong color wire, the lead wires are new. the black bobbin looks straight outta the factory. and the pole pieces were relic'd and blackened via sharpie!
this is the true color of vintage Fender formvar wire, a rich gold. natural wear.
in comparison, 6 other pre-63 pickups. you be the judge. Of course, I had to file with Paypal blah blah. To add insult, the seller accused me of willfully breaking the pickup so I could send it back for a refund, and to this day won't admit it's a fake. Buyer Beware!