first u need to know is what movment u have , like is it asian 7750 or swiss 7750 , then u can either fix it yourself by getting u a new stem and removing the broken one , if u need assistance just pm me and i will try and help u , its not too bad unless it broke even with the crown if this is the case u may either have to get a new crown as well , it is possible to get the brokens stem out sometimes just depends how stubborn it is basically
joe