Oops, I hadn't realized we were talking about a gun someone had posted here or on another board. It is none of my business what you price your gun at, and I have no criticism. I thought we were talking about "some" gun in some shop somewhere, otherwise, I would not have commented.
As far as I am concerned, an out-of-production, high quality gun is worth exactly the price at which you are willing to sell and someone else is willing to buy.
Certainly, extra magazines add value as well.
My apologies.