Md State Police S&WModel 19-357 Value

I'm trying to help a fellow retired Maryland State Trooper to establish a value for a NIB 1985 S&W model 19 357 Revolver. Gun is a 50th Anniversary Maryland State Police Edition (1935-1985) with 6 inch Barrel,adjustable rear sight with a red type of front sight, in display Box.Stamped with MSP #. Gun is 100%, cleaning kit tool & wooden box.Please reply to tcl2b@yahoo.com