Hello Karen!!! I owe you pictures from Mobile!
You're on the right track with matching the holes with similar holes in the bulkhead (that Darrin is gold when it comes to good advice... too bad he drank waaaay too much torpedo juice...
).
This looks like something that would have been made aboard a tender under the direction of the yeoman or such. If it were EB original it would be stainless steel and be the equivalent of a Rolls Royce Silver Phantom... so I don't think any other sub is likely to have something like this. But I am not always on the right side of an issue. My only input here is DO NOT LIMIT your search for hole alignment in the officer's quarters. Your boat had the Seafoam green paint in all crewspaces in the 1950s when she and COD were running around the Atlantic and Carribbean pretending to be Russkies. This box could easily have been bolted in the crew's mess for certain requirests. Also, the black plastic sign on it looks post-war, more for its size of type, etc., than its construction. But if this were original equipment, it's tag would be engraved stainless steel. Likely what happened was that sometime back in ancient times, someone bumped their elbow on this box on the tour route (or didn't) and some numbskull thought it should be removed for safety reasons. So my gut feeling says maybe in the companion way outside the yeoman's office... if not in the crewsmess. Good luck with the hunt!
Darrin: can you ship me a gallon of the TJ? My nerves are a wreck...