I’m looking at a 1956 flattop .357 4 5/8” that is unconverted. It looks to be in very good shape except the rear sight blade is damaged and needs to be replaced. Only minor handling and light holster wear. The bluing and anodizing looks good, but there is some holster wear at the usual places. No box, just the gun. Any ideas of what a fair market value of the gun would be? Thanks in advance for your help.