Not trying to derail, but, are any red dots made in America?
I picked up a used T1 last year. If a used Aimpoint can be found that’s always a great option.I have seen the PROs go for $300 used. You'd be hard pressed to beat that in your budget especially since you already have one.
Primary Arms and Vortex make good stuff as well for a bit cheaper.
But in your shoes I'd definitely get another PRO.
Trijicon and Leupold I know for sure. Vortex makes some of their optics in the US but I'm not sure if any of them are red dots.