I read that millet stopped making rear sights for smith revolvers. I was able fo get one of the behlert rear sights and was hoping to find a rear sight with no sharp edges for better carry as well.
Be careful with the aftermarket sights still available as I believe they are all made to fit the newer style topstrap cut with the rounded front. I think SDM is making one too but, again, for the newer style I believe.
Millet no longer makes the old style sight square tang single screw, if you look around they will show up from time to time.
Bowen's like the new Millet require holes drilled and are designed to be a direct replacement on newer Smiths.
Weigand makes an adjustable rear sight blade that work's very well and gives you a large flat non distracting area. I am very happy with the one I have.