The Ref. 5512 from 1959 has pretty much all the things we'd try to look for on the current Submariner. Its case had developed to 40mm, up from your 37mm to 38mm of before pieces. Crown-guards have been added, and the bezel now somewhat overhung the side of the situation https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/