The 5512 follows the same pattern as the 5513. The watch you are showing will date between 1964 to 1966. There is a high chance it also has a 5513 case back. What you need from the watch to date it is the serial number most likely between 1.1 and 1.4 to be on the safe side. The case back will be 64 / 65 or 66. The case and dial are the key elements. The bezel less so other than as you noted for signs of over polishing to the whole watch.
We will wait to hear more details.
Best
Bill