johnmcl:
Fixed sights, .357 magnum, stainless steel, 4inch partial lug barrel would be a square butt Model 65 .357 Military & Police Stainless.
As above, but full / heavy barrel under lug would be a Model 681 Distinguished Service Magnum.
Either way, it was manufactured in late 1989 or early 1990. Guns in the BEPxxxx range shipped December 1989, guns in the BFNxxxx serial range shipped March 1990.