Suggest using another winch
I'd suggest you not use Maxwell, even though that is original equipment. The web site given above is the correct one to get spare parts. I recently had to get extra springs. However, Maxwell is no longer in the sheet winch business and this company (website) just bought the parts. Plus, they're all the way across the Pacific in Australia. You'd be much better off buying a name brand winch from West or another discount supply house.