Condition, condition, condition.
Do you have the box, the envelope with the fired cartridge (unopened)? All paperwork and even the plastic disc and bag the gun came in? Does it have marks where the rings were attached or are the rings in the package unopened? Is the gun NIB or does it look like someone drove tent pegs with it or is it somewhere in between? Since it has a rubber "handle" we know someone has monkeyed with it and it is not NIB. The grip locator, disassembly pin and grips would have to be obtained at some expense.
In today's market, I personally would not pay the prices quoted above for anything other than brand spankin' new in the box. And I would have to think about it long and hard at that. New ones are out there. I got my 7 1/2" new for $440 plus tax from a shop 3 years ago and my used 5 1/2" also from a shop last year for $436 out the door. Robert