I just had a similar thing happen to me: A guy that I have know for 6-7 years, he goes by the name "Vietnam Charly" around here and drives a pick-up truck that's missing the driver side door ....
He saw my 1665 GWSD and checked it out. Then he told me that he has "one of those submariners, but it has no date and one of those with the red and blue ring around them".
Turns out he bought both of them while he was in the service in the 60's and when they stopped working he sent them to his son in Arizona where they are sitting in a drawer .... I already offered to take a look at them