This is a 1938 ladies Bulova. It has a 17 jewel 7AM movement in a 10K rolled gold plate case. The band could possibly be the original. I don't have the crystal measurements because I took these photos a few years back and don't feel like searching through 1000's of watches trying to find it again.
Gosh, that's a nice looking watch Alan, looks like it didn't see much wrist time!
I'm going along with Ken on tagging it as an American Girl but without the "F" variant. It's really hard to see in that advert but I think the F had even only numbers. Here's the same watch in a Canadian advert that's a bit clearer. It's called the Canadian Girl F here but that's because this ad was used in Canada only.
http://www.mybulova.com/sites/default/files/vintage_ads/bulova-ad-1939-…
1938 Bulova American Girl