What my own research led me to: https://www.viewsonic.com/global/products/commercial-display... (OS-Free Commercial Display, all sizes available) + HTPC.
(Assuming you've already bought one and have been using it for a while)
Have you tried using the built-in speakers or have you been using external speakers the entire time you owned it?
I'm curious if the (specs say 10watt) built-in speakers are in any way usable -- my criteria would be, can you easily hear dialog at the normal viewing distance; I wouldn't hope for hi-fi sound suitable for music.