Has this gun been reblued or refinished? Something doesn't look right--the barrels, barrel band, and some of the screws appear pristine and the wood redone, but the casehardened receiver appears aged. Or is it the lighting? If it has been refinished, no matter how well done,or had parts replaced, that will negatively impact the value.
A second variation in excellent (untouched) condition is worth $1,000, very good, good, fair and poor condition worth $650, $300, $150, and $100, respectively.
If reblued, parts replaced, I'd put it in the $300 range.