Les, Finding replacement sights for handguns is not a problem at all.
There are a lot of options out there. Finding what you describe would definitely be a challenge.
I’m having trouble understanding why you would want what you describe ???
Please give more info !!!
As for defensive shooting, keep a few things in mind when your thinking about swapping out your sights.
First, most self defense shootings occur at arms length. (no sights needed)
Two, If not at arms length, it’s usually within 10 feet. No aim needed if you learn to point shoot, like you should be at that distance. (no sights needed)
Third, if it’s beyond 10 feet there’s a good chance it’s not self-defense !!!
If you like fiber optic sights look into the ones sold by Dawson.
If the eyes are going bad, a laser is your best bet for defense.
If it’s just for fun, a holographic or red dot.