Old hardware

I recently moved to a small town in western Wisconsin and into a 100+ year old house much in need of repair. One of the items I'd like to find in order to keep the project historically accurate is storm window hardware. Are there any suppliers left in the US which make the old style hardware or am I relegated to searching salvage shops? If I can find a supplier, I'd like to start up a side business doing repairs for the dozens of needy clients in my region.