I purchased this Hampden watch on ebay today. It was noted as being a 1940s original Hampden but I have failed to find any evidence that Hampden manufactured any watches after 1927. As you know, the Dueber Hampden factory was shipped to Moscow in 1930 and became the start of FMWF. There are mentions that some movements from FMWF was marked Dueber Hampden at the beginning of production. Could they also have gotten a few Hampden dials ?
Not as intriguing, but my guess is that this is probably a late 1920s dial, perhaps in a newer case. I will update you on the movement when it turns up.