What you probably have is a roadster mirror, no door on a roadster so the mirror was mounted on the fender. If you have one in good shape that your not going to use, you can get pretty good money for it. They are pretty rare and in demand for someone doing an original roadster restoration. They make reproductions now and I think they run about $200. I have a 66 roadster but my roadster mirror was long gone before I got it. Post up a picture of it!