Welcome aboard sidney! Sorry I can't help you with the parts. IIRC Minnesota is a very old Sears brand and there may be other machine brands made by the same manufacturer that will have parts that fit too. Others here will know more. Pictures will help them identify who actually made it for Sears. You can attach pictures from your computer by using the square icon that's three over from the smileys.
I hope you plan to stay a while. This is the best forum I've found for people interested in old sewing machines. Old sewing machines are fun to use. It's hard to have just one.
Rodney