What are you looking for? Do you want direct cowitness (meaning seeing the red/green dot through the rear sight inline with the front sight). Or having the red/green dot over the top of both rear and front sight?
I have a direct cowitness set up on my Z5RS using the “ MFI Ultra Low Profile Mount” from Hkparts.net. LINK: https://www.hkparts.net/shop/pc/Ultr...s-91p17962.htm
For the optic, I’m using the “ Holosun HE503GU GR Elite” that I purchased from amazon.com when it was on sale. I plan to get another once it becomes on sale again. LINK: https://www.amazon.com/HOLOSUN-SG_B0...NsaWNrPXRydWU=
Here’s my optic set up on Z5RS. I plan to do the same on my POF SMGPK SBR.