Elgin Pocket Watch Opening

How much is my pocket watch?
I opened an Elgin watch face that was made in 1929. It has 17 jewels, 387 is a grade, 16s size and looks and works well. I do not know if the case has a gold content or not. It seems possible. They offered me $ 75, but I do not know about these watches. I do not really even know that I want to sell. I guess it depends on what is really worth.
Watch is most likely to dollars ($ 120) with 17 jewels chance to sell
JUDO Elgin Open 2008