I put a PA 1X prism on an upper just recently. I like the etched reticle that doesn't require power, and the diopter adjustment for older eyes.

Haven't put the light on yet, but soon.

https://www.primaryarms.com/pa-1x-compact-prism-scope-with-acss-cyclops-reticle-fde

[Linked Image from i.imgur.com]