If you want to take a departure from "100% original parts", consider a Marbles "bullseye" aperature rear sight. It replaces the rear dovetailed sight, and has an elevator ramp. It makes a very friendly sight for older eyes. I have one on my Higgins model 50. It is a great back-up sight system to my 4x Leupold. Cost = $20
It comes in a long and short version. The longer version is easier to adjust slide movement. The short leaf version can be a bit stiff to move the slide ramp for range/distance adjustment. If you don't like the outer ring, you can cut/file it off. Nice sight.
https://www.midwayusa.com/product/1828132532/
