No experience running them, but looking at samsung digital signage, HDR looks to be a feature of their high end models and extremely expensive. ~$4,500 for a 55" 4K TV [0]. The more competitively priced displays[1] (~$1300 for 70" 4K) don't seem to offer it.
Amazon has a bunch of affordable models from Samsung. Haven't clicked through them all but here's a 65" with HDR for $600.
https://www.amazon.com/Samsung-Business-Software-Speakers-LH...
However, it's probably not the sort of "dumb" TV we want:
Seems like this is interfacing with some sort of app on the TV, so I suppose it's not a dumb display.