If going cheap, like rbernie said.......Primary Arms.
Had one, worked fine.
My next one, should there be such a purchase, will be an Aimpoint.
I have a Leupold RDS.......it was 300.
Heavy, and on a rifle.
The Aimpoint would be my choice if setting up a deer pistol with a tube style red dot.
It worked well on my TC (Primary Arms)......in .223 and .35 rem.
The gun shot so well in .223 that the 3 MOA dot was too big.
That dot size was fine on the deer bbl.
I'd go with the newer versions w 2 MOA.