I just bought a vintage wristwatch in mint condition, with the name National on the dial at 12oclock and Eisenhardt mfg co engraved on the movemet. Apparently Eisenhardt mfg co was located in St. Louis and used to import Zodiac. But I have no info on where their movements (ie, those of Eisenhadt mfg co) were made. I cannot find any info. Does anyone know anything about this company?