Where would you find information or a list of compasses from a World War 2 Japanese Sub?

There are several submarine museums such as the U.S.S.Ling In Hackensack, N.J. known also as the Naval Museum. They have a small (Sea Hound) type U-boat with cutaway panels 9craft has a Mercedes-Benz Diesel and recently Exide Batteries- certainly Not original gear!- Everything that went into a submarine is of the maximum as regards quality control and accuracy-including certainly compasses. Submarines do a good deal of (Blind navigation) and the compass is mandatory to be of the highest function. Most US subs use or used Sperry Gyrocompasses which were specially made for the Submarine service, looked like drum-shaped robots with the large master motor-generator.-was run all the time except in possible 9Silent runs) when the whole sub was powered down and the Gyro was cut off ( a very dangerous maneuver as if the sub had to suddenly maneuver (say a hail of depth charges!) navigation would be (By Guess and by gosh- say, we were at 270 Degrees (Due west) when we cut off the gyro, back about l5 minutes, H"mm guess 265 average. not a good thing. they had magnetic compasses for such emergency use but normally navigated on the Gyro-compass or Iron Mike ( so called because of the stainless steel construction, not the boxer. Good luck. I do not know of any Japanese compass makers, you would have better luck with surface ship gear more survivable- but many Jap subs were captured intact while under construction at shipyards_After the Fall of Japan Good Luck- BANZAI! By the way Maru applied to a Japanese ship is dErived form Japanese Word for Vessel (includes pots and pans also!)

I have a Japanese naval compass in my possession that was made by the "Oki Electric Co. Ltd." the company is still in business but unfortunately the were not able to provide any info on the compass. It is a gimbel mount compass and made of brass measuring 3 1/2 inches in diameter. It is air filled (not liquid) and magnetic instead of gyro, and inside seems to be a coil of wire that I assume was to cancel out interference from shipboard electronics.