I have this orphaned case. The back is marked Waterproof to 666 Feet. Self winding. Antimagnetic. Stainless Steel Case.
The unusual thing is, as can be seen on the photo, is that the case appears to be mono block style. In that the case back does not remove.
The interior of the case back is marked as follows:
11H 9206 11HC
All of the markings seem to be Bulova marks (I assume).
The case design would suggest it is mid/late 1960s to early 1970s.
Any Ideas ?
Not being able to see your photos I would say that we have no way to be certain. Bulova never advertised WATERPROOF to any depth. In the 60's and 70's they put 666 or 333 on dials indicating water RESISTANCE to 100 or 200 meters. Prior to that they placed the word WATERPROOF on dials but US law forbade it after 1968 (ish) and the word RESISTANCE was used. Almost all Bulova watch cases produced for the USA market were imprinted with the name BULOVA on either the inside or outside. Bulova did market some SUPER WATERPROOF case in the mid 60's but they are less common.