I promise the other guys here that I will try to buy some kind of soft metal / alu rubber/polish, and first do my very best, to try keep them original.
But if it does not work, that copper will be removed, and rewrap them with something else. Of course, if I have to recover them, I will try to find some wrap that Slingerland was used at the early 70:s.
But at the moment, they have to stay a while as they are, I am in the middle of restoring my Psychedelic Red Ludwig.