Not sure about the US but a VIN less frame is not worth a great deal in the UK as you cannot register the bike unless it is on a 'Q' plate which massively affects its value. The VIN number near enough triples the price of the part, as you are effectively buying the identity, which is crucial for any hope of a resale or maintaining the value of a bike towards a half reasonable amount. Even then if it is not the original VIN or it does not correspond with the engine number according to the log book (title of ownership), people are going to ask questions as to the history of the bike and most will walk away unless its destined for the track alone. Good luck with the sale anyway.