My fender tag was "liberated" while in storage at the prior owner's. I don't have a build sheet. Met a guy at the 'nats that repopped them. He looked at the car and as I wanted a tag as it was built not as it sat (air grabber, rear wing were not original) he was cool with it and made me one for a reasonable price - he said if I had tried to make a tag that was not correct for the car as-built he would have told me to take a hike, didn't want any part of a clone or a scam. I might be able to find his address - let me know if you are interested.
I would go through Galen.I have seen alot of fender tags the last few years that are clearly repos.The font is all wrong.Letters and numbers usally to small and too thin.