try to post a bigger picture, so we can compare fonts with originals.

It could have gotten stripped and re-lettered with black lettering.

Even if body numbers match, body numbers only include sequential, tag could have been forged from a 318 to a 440+6 letter in VIN.

If he as build sheet it would help, same for fender tag, but fender tag could also have been forged.

ASk seller if he as other documentation or if you can talk to prior owners.