That is a 4th Change 32-20 made in the mid-1920s. The 4" barrel is less common and the condition looks to be a solid 95%+. From your pictures, I can not see any area that has lost it's bluing except maybe around the muzzle. Grips look very good as well. 32-20 is a great shooting gun and I would say it would be valued at $400 to $500.