Check out this company. It's called Hagan Street Rod Parts. They make and sell some awesome fuel filler doors. Here is a link to their site. Check them out.
http://www.haganstreetrods.com/
I have seen the type of fuel door you are talking about. All of the one's I have seen have been hand built. Hagan's is right down the street from my house. About a year ago, I mentioned they should make the filler kit. I don't know if they took the suggestion but, here are some alternative styles to look at.