This thread is kinda getting hijacked, but I'll throw in my $.02. I figure a running 750 motor is gotta be worth between $500 and $700. As for "those" kind of buyers, here's a story for ya....
I'm into harleys, I know an old time biker (read covered in tattoos, grey hair down to his ass, beer belly and bad attitude and about 6'6", i'm not going to get into affiliation) that was at a swap meet selling some parts. He had a set of heads off of an old panhead (1950ish). Punk comes around and tells him they're worth $50 and he wouldn't give him a dollar more for 'em. He picks up one head, throws it down on the pavement at the guys feet, it smashes, does the same thing to the second head, then says, "ok, $50 right now a**h*le" . Sounds like an urban myth, but it happened. Now, I wouldn't do that with my 750, but after hearing that, ya kinda want to don't ya ??