It seems to me that there's a thread here on OldMiniBikes discussing the newbies asking how much a bike is worth and that one should not ask members on this site for such information. If that's the case, then why are there so many members that are eager to tell you how much your bike is not worth??? hmmm
The engine spec number you provided is one of the 2 correct spec numbers that were used for the Black Widow. The "star" on the back of the seat that you mentioned is, in fact, where the original red reflector was mounted on the back. The seat cover had a small "X" cut in it with a carpet knife. The stud on the back of the reflector went through the seat cover into an opening in the frame and was secured with a small metal backing plate and a nut. And although it's been repainted red and has some other items that a purist(such as myself) might not be interested in, it is nevertheless a nice looking bike. Although I don't like to see bikes parted out, I can tell you just the Dellorto UA19S carb and the original intake manifold would easily fetch close to 400 bucks and we haven't even discussed the engine, TC-1 assembly, tires, etc. Remember, there's an ass for every seat. Even as a customized bike, I'm sure a buyer will come along that will appreciate it and with possibly a little negotiation, it'll find a new home. Don't let the opinions of others deter you in your asking price. Live it Rupp!