1941 Hudson Commodore 8 parts

Any number of people.  They usually specialize in one thing or another for Hudsons (rubber reproductions, clutch parts, engine parts, and so on).  No one sells everything.  If you can be specific on a few things you need, we can suggest suppliers. 

You could start here, at the Hudson Repro Parts page.  http://www.detailedconcepts.net/Repro_Table.pdf   This contains not just a listing of specific parts that are being reproed by various people, but has a list of the specialty Hudson vendors as well.  For stuff like used body and drive train parts, you would need to obtain a copy of the club magazine with ads for vendors in the back.  If you intend to keep this car, you might find it helpful to join the H-E-T Club and get the magazine.