Comment by psd1

Me too, in the general case, but the square display was a key requirement. And i can see it; op is displaying LP covers; it needs to look good

I think i'd just make the bezel for the display and putty an SBC onto the back with an HDMI converter dongle. I'd likely order a custom picture frame with some rococo moulding, for the anachronistic effect, and display nondescript oils when not streaming.