https://sjhardware.com/product/ggap-...10-x-12-plate/
As far as recommendations go, it depends on what your intended purpose or role is. As a general rule, I set up to have 3x rifle mags and 2x pistol mags, and med supplies available on my carrier as a bare minimum, and then go from there depending on what i'm going to need for the day/weekend/course/etc. It also depends if you're talking airsoft or real steel.