I suggest an optic, red dot is my preference. You can machine the slide(expensive) or get a dovetail mounting base. Ever since I put my Burris Fastfire II on there I have never even considered going back. Target acquisition is faster on the draw, less strain on your eyes, and no having to align sights. Put the bead where you want it and pull the trigger. Not that expensive either. I got the mount and the sight for $275. And as you can see I have the 9c and even with the sight I still rock my Galco IWB. The red dot clears the holster all together. I get a pic up later of what it looks like when I'm wearing it. Get a sight, you'll thank yourself!
.22 is too weak for Red Dot if mounted on a slide..