" I intend to run as small a set of lights as seems to look about right on the bike. "
____ Okay then, how are you expecting to find the electrical-parts you'll need ?
Are you only interested in original-type stock charging-system parts, or what ?
I do have a fair sized stash of spare parts from a local motorcycle salvage yard that went out of business in the early 1990s. The salvage yard got much of their stuff from the local Ducati dealer that sold of their bike salvage in the mid-1980s. At one point I bought a couple of salvage engines complete for about $50. A couple of original Mk3 megaphones were $15 each. Spare frames were about $20. Man, how I would like to walk through that salvage yard again with several hundred dollars in my pocket!

I also picked up some incomplete bikes during that time that I pulled apart. These were the old square style bikes that nobody much wanted. I do have some scruples about scrapping old motorcycles for parts, but when major parts are missing I don't mind stattering an old bike for parts I want.
I still keep an eye out for old Italian stuff at swap meets. A lot of the old rebranded Italian stuff (Wards Riverside and Italian Harley) can still be had fairly cheap. Even Benelli and Aerrmacchi is not that expensive. Since Guzzi and Ducati are still in production and still imported, the prices are usually pretty stiff.
I also do know a local collector that has quite a stash of NOS Ducati parts from defunct Ducati Dealers.