I asked this question because of a watch that was offered by a good friend who inherited it from his father 20 years ago. The watch is a Rolex Sub 5513. The production number is 1.4m but stamped between lugs at 12 o"clock is "orig rolex design" and not "registered design". As I understand, the "orig rolex design" stamping came out in the 7m serial or around 1980? Any idea about the discrepancies?Don't think so.
I know and that is also my opinion but its more of unlocking a puzzle to me. His dad told me that he bought the watch in the early 80s from a friend. Could it be that the original owner brought the watch to a Rolex Center and had it restored? Btw the dial is also a later model with white gold indices correct for an 80s 5513.Frankensteined watch would be my guess.