I see a lot of these posts so I apologize adding one more to it but I’m not familiar at all with guns of this type and I want to make sure I have all the info right. I can post pics if needed but I found a website that listed serial number ranges by models/changes, is it as simple as that? The serial is 64xxx, black body with what looks like an ivory grip. I understand it to be a 1906-1909 second model, second change? And if so, what would a ballpark value of one of these be? It looks damn near perfect, it’s in stunning condition if I’m holding something 100+ years old.