A rather fundamental piece of information to omit.....
It was this fella here, still available at EBuyer for £500.
Very nice screen for £500, and you definitely don't want to go smaller than 32 inch at 4K as you'll need to start using scaling to be able to read text and stuff, which would rather negate the point of the whole endeavour.
https://www.ebuyer.com/810693-lg-32ud89-w-32-class-4k-uhd-ips-led-monitor-32ud89