I might be wrong, but I don't think Model 19s were ever stainless. Nickel maybe. The stainless version was the Model 66.
Depending on where you are and the condition (and serial number) of the revolver, I'd put it between $250 and $400. The holsters don't add any value to the deal, but might be closers if someone's on the edge.
-Don
(Ahah! I saw you change that!)