[40cpe]

The pictured wing nut is a "type D style 1" according to what Google finds. I didn't find any fine thread wing nuts like that. If the original style is important to 39portlander he might have to get creative. I can imagine turning a hex nut to the diameter of the threaded section of the nut, drilling out the damaged threaded section in the wing nut, and welding the new threads in.