I think you need to start at the Pocket watch data base to get all the information about your watch. Go there and type your watch serial number into it . The site will tell you model, jewel count etc.From there you can search Ebay for the correct model , jewel count & with all the information you have.
I'm sorry if I am repeating things you know but I am just assuming, correct me if I'm wrong.
Here is a link to the data base. https://pocketwatchdatabase.com/
Now you can begin