Mine's a rare one. I talked to Gene and there's no number on it, but he remembers doing it in the 70's, because of the high "e" bender. So mine is mystery #?
To add to it, I have the chrome back plate and it has the String Bender logo and the US Pat 3,512,443
The tele is a mystery as well, the best I can figure, it's a 58-60. Bridge top and through loader and jack are original. The binding was replaced during the refinish after the bender was installed. I've seen a few pics of original ash Tele Custom's, so I'm not giving up on this one.