This the only discribtion of an S&W rear I am sure of. S&W rear in my experience are model scinsetive .I've got a S&W 357 magnum stainless steel revolver w/4 inch barrel. Have no idea the "frame" designation. Recently dropped bending the rear site. Looks like 2 screws keeps the site secured. Just trying a shot in the dark to see if anyone might possibly have one for sale.
The S&W rear sight windage adjustment is a screw with a nut on the left side. The screw goes through the rear sight and that is the only part of the rear sight that it works on . The nut on the left side is what keeps the screw and this the sight solidly in place. The windage part of the sight is not model scinsetive and is easy to replace. It takes breaking the nut off the screw so the adjustable part slides out. The replacement parts are the the sight part, screw and nut, maybe the detent plunger and spring if those escape. You can try for a complete rear sight and hope the screw placement into the top of the frame is the same or replace the adjustment parts. The nut is a round internally threaded part with screw slots in it the end of the screw has a shallow hole that when the nut is adjusted correctly is swedged into the the nut to keep it locked in place, that is why the screw ends up broken when replacing the windage blade. The windage parts are fully interchangeable where the complete rear sights may not be and as I said earlier model specific to many time in my experience.
Brownells should have all the parts you need.