Oh - I really thought it was one out of a lot and the note about the rear sight was just about the one they happened to have photographed. I'll be requesting a refund if anyone wants to keep an eye on it. I'm sure it's still well worth that price - just being particular.
When the item # matches the serial number, I believe that means they only have one. The transferring shop would probably buy it for $250. But I’d keep it if I were you.