I am blessed with excellent long range vision, it's the close stuff that gives me problems. I knew it was coming so over the years I gave a lot of thought to what I'd do when I could no longer see well enough to shoot. I am a hunter now but I used to shoot a lot in BP matches, and I regulary do a lot of shooting on my home range, so I knew the end result I wanted to achieve.
So just a few years ago I checked the sights on my .54 and .40 flintlocks and I could see to shoot fine. But that same season around christmas I shot the .40 in prep of a squirrel hunt. To my dismay I could no longer shoot accurately, there were 3 distinct lines where the top of the sight should have been.
But I was prepared due to thinking about it. I made up a few peep sights I had been thinking about. These were to be small and unobtrusive, almost like they were meant to be on a longrifle. They have a small amount of verticle adustment, windage adjustment is by the front sight. The key for windage is how accurate I can drill and tap the center of the tang. There is a good bit of hand work involved but I'm a retired Tool & Die maker/Aerospace structural data SME , so it was no big problem.
I have it on both my .40 and .54 and the next rifle I build will have one also.
My vision cleared just as I needed. I know my peeps could be fancied up but I like them as they are.
No I am not selling them.