Very little is known about the SUB 500 Searock. The general feeling is that it was never a production model and even Doxa have no details of the watch. There is no doubt that the movement, bracelet, hands and case back are genuine Doxa parts. The symbol on the case back is similar to that on the Ladies 200T Sharkhunter. This would indicate that it is from the Synchron days of Doxa and dates it to the early 1970s. Unfortunately this makes it more difficult to authenticate because a lot of information on models produced, quantities and designs from that era is not available anymore.
It is entirely possible that the watch was a limited production model, however, it is also entirely possible that the watch is a hybrid, put together from Doxa parts, with an unknown dial which was refinished to show the Doxa lettering. Whatever the origin of the watch, I have included it because it is unique and even if not produced by Doxa, is testament to the power of the brand and the image of the orange faced diver which Doxa gave birth to.