ASrock desk mini has vesa built in and comes with a power brick. Might be easier to just get a custom side panel made with vesa mounts for a K39 or a Skyreach. Velka case might be a option too once the side panels have holes in them, as-long as two holes line up with vesa. I would also say HT5 or the Smaller Geeek case but idk how acrylic would hold up.