Junghans mantel clock with Westminster striking mechanism quarter hour circa 1930s?

I have a Junghans mantel clock with a Westminster quarter-hour chime from around the 1930s with a Junghans W64 movement. The clock works and has a very nice sound. What does 50 3 next to the Junghans symbol actually mean? What is such a special mantel clock worth? It is very rare to find one….