At one time there was a kit that could be had which used a powder and resin mixture which you did yourself, very similar to acraglas, in various colors and was used to fill front sights in the S&W manner. It was very good, quick and long lasting. Much easier to do than cutting plastic inserts to replace those that came out during shooting. I suspect that somebody still makes something like that since it hasn't been that long since I saw those kits for sale but don't recall where exactly. Lots of colors were in the kit including green and yellow as well as orange and red etc. A colored resin filled hole should last virtually forever.
