I too have lusted for a yellow RB-1. One popped up for $120 in my size a few weeks ago. The seller told me I had first chance at it. A few hours later he wrote me with this lame story about how he doesn't know that much about bikes and its actually an mb-5. Whatever. He deleted the post but i know what i saw without any shadow of a doubt. He probably just realized what it was really worth and pulled it.

That's my rant.

You should totally tape a note to it. Tell them you would love to buy it. If its really being that neglected they probably don't know its worth or care that much about it.

Good luck!