If you built it, is it a Fender Telecaster?! /emoticons/default_biggrin.png
Ebay usually shuts those sellers down pretty quickly, although some of them are persistent. Fender has people who comb the internet looking for that kind of stuff and tend to make it go away in a hurry. You may also want to try the various gear or Fender forums - some of those have some guys who make and sell pretty nice stuff. Expect to pay $25-$50 for a top-quality silkscreened repro decal these days, but if you don't mind a blurrier laserjet decal, those can be had in the $10-$20 range.
Try a search in any of the various Emporiums under "Decal" or "Headstock", and you'll probably find somebody. Most sellers try to keep a low profile either because they've gotten a letter from FMIC or because they wish to avoid one.