Hi, Eric - welcome!
All I can offer is that it looks most like a custom Bianchi Cup revolver built on a S&W Model 10.
The optics base and fixed sights under it rule out PPC.
It's possible it's an ICORE Open gun, but it'd likely be using moonclips rather than speedloaders. I can't tell - has the cylinder been machined to accept moonclips? Does it look recessed like the one in the pic below? If not, it's unlikely to be an ICORE Open gun.
Is the barrel marked? Maybe someone will recognize it and the other components.
A 1/2 to 1 lb trigger? I assume you mean the single action trigger.
As far as price, used PPC revolvers turn up occasionally and generally sell for $350-$600. Pretty good price for what they are. I tend to think used Bianchi Cup revolvers would fall into the same price category. If it can be documented that it was built by a well-known 'smith, and it's still in great condition, it can go for more.
Have you shot it? It ought to be a tack driver.
