The serial numbers on your watch date it to 1940. That date is consistent with the era in which the dial, with the lumed, stylized roman numerals, was used. Here is an example of a somewhat similar dial on an Aquasport from 1940-41 (source eBay): I have also found a photo example of your dial on a pocket watch dating to 1937-39, but cannot quite tell if this example has been repainted: (source link) Co-signed Omega/Tissot examples are more often found in the South American market from that time, but these co-signed markings are also commonly faked nowadays.