I have a B&T Glock chassis with a red dot for 9mm/40/357 sig glocks (model BT-430200) with a PA ACSSG2 etched reticle red dot.  These chassis are usually not in stock to buy, BT doesn't make a lot of them for some reason.  Works with Glocks gen 3-5.  

https://www.eurooptic.com/b-t-usw-g17-conversion-kit-for-glock-17-with-rail-bt-430200

https://www.primaryarms.com/primary-arms-slx-1x-microprism-with-red-illuminated-acss-cyclops-gen-2-reticle

Located in East Mesa.  480-343-1917, text or email works best, I don't pick up unknown numbers.  $650 OBO