That is a tough call because of the fact that they are so rare, that perhaps not that many people have heard of it. Maybe put it on a gun auction site with a lowball starting bid like 4-500$ and give it a good writeup. Like, give as much history as you can glean from the info here and elsewhere, make sure it is real clean and good looking, not necessarily polished, just clean and oiled without finger prints etc. Then take real good pictures of it. Fuzzy pictures are bad news. Mention the bill of sale and whatever else you have. Well look at some of the nicer listings as compared to the crummy looking online listings. Run the auction as long as you can, well not three days or something like that, you need to get exposure time for everyone to become aware of it. Use title for listing like RARE Witlow revolver or the like, to grab attention. Maybe you have ebay and know about listings? If you start with a too high price, on an auction, some folks will just pass it by and not look closely I don't think. But they might get into it and bid it up to the price you want.