Hi there! Recently picked up this 1973 military Hamilton. What is puzzling me is the case back, I cannot find another Hamilton Royal Navy watch (0552) that has this size lettering and layout on the caseback. I'm certainly no expert on military pieces though I still can't find any case backs with this size lettering and layout on any 70s military watches. Runs off a cal 649 and yes I am aware of the replacement crown and relumed hands. Hopefully some of you military watch guys can shed some light on this for me! Thanks in advance