To be honest unless you are getting a high fresh rate panel you dont really need HDMI 2.1
There are some good deals in the b grade sale for 4K 60hz screens that would do.
https://www.overclockers.co.uk/clearance/monitors?sPage=1&sSort=3
From what I understand they are mostly customer returns, you would still have a your 2 week return window if you were not happy with it so better than buying second hand IMO.
There is a thread with details on how to make offers on them too if you have not seen it yet.
https://www.overclockers.co.uk/forums/threads/niks-annual-b-grade-blowout.18922428/