Look in Hemming's Motor News. There are many shops that repair all these type motors around the US. Pick one closest to you. I have one I use for starters here in Illinois, another I use for alternators, a third for generators, and yet another for small motors. Each shop has a speciality.
I have often collected bad parts just to get part of a part. Obviously it would be better to get a complete unit that works but these old parts are hard to find. I presently have one wiper motor of one type/brand and another Marelli that apparently was original on the Alfa 6c 2500. I hope to get another Marelli before I resort to an expensive motor remanufacturing to make them work.