ebay for the headbadge, or maybe just as cheap, a craigslist find. I do not think there are any reproductions.

A "collector" might want an original finish, as this was not a historic bike, no one won the Worlds on THAT bike, the goal is what will the family member get excited about? Go with that. I would locate transfers / graphics before you remove any paint, saves problems, photodocument the locations, measure color breaks if any. Memory only goes so far.