@Steve Morley
Look we really wish that you had that watch, and would be even more impressed if you could retain ownership of said watch. Looking at it from very informed non biased eyes, there is no way yours is the watch you want it to be, just from what you have provided.
There are multiple problems in the documents you have provided. The delivery date is way to late, is a big one, as it is common knowledge they wore these watches during the training program, and it has been photo documented in the years proceeding the missions, some members here have talked about the history of the watches with the actual astronauts and confirmed when it was received, if it was the same one during training, and the disposition of the watches post mission. If NASA or Omega could confirm it as the correct watch they have no reason not to, they recovered one of the lost watches last year in fact from South America. My understanding is while yours is marked with a number it is missing the rest of the NASA added engravings in the correct style, and does not match the correct serial number that is not common knowledge.