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The price you mentioned must be after taxes,,, & out the door,,,,as it's an odd number. If I'm correct,,, my next question would be, "Has it been converted to the transfer bar safety system?" I saw a shooter grade Flattop 44 recently,, priced at $575,,, but it had been converted, and a proper set of part re-convert it back to normal will set you back about $200. Overpriced if that's the question.
A 3 screw Super that's been converted, w/o the original parts will cost you about the same $200 to get it "right." If so, I'd say that the gun in question is overpriced.
Next, if not converted, the next thing is condition, condition, condition. Study it closely. Has it been cared for, or abused? If you do not know how to really look at a SA revolver to look for flaws & such,, ask a friend who is well versed in them to help. Re-blued, or not? Rusty barrel inside? Does the action time up correctly? Is it worn & beat up looking,, or just honest wear from casual use?
An educated buyer will know what is best. The more details you can provide us here will help us give you a much better idea of it's true value.