Question Looking for a DSI display and a compatible case

One of my ongoing projects with my RasPi 3 is making a little retro gaming box. But I also want it stand-alone in addition to being used over HDMI. So I've been looking for a DSI display and a case to go with it. I want to keep this as small as possible, so 7" is the largest I'll take, but smaller is better. I don't care about touch screen capabilities or whatnot.