Pretty sure this is the same one I got for work when we got a shit load of HP screens with no stands for cheap (it turns out that 2nd hand HP stands are actually more expensive than screens).
Paid a similar price via amazon.
Although the moving parts aren't very elegant, it's pretty sturdy.
I think Amazon might be a pound or two cheaper. But in general I'm trying to reduce the amount of money I give to Daddy Bezos. Yesterday's Tado splurge (Owning Your Own Home thread>>>>>>) has made me feel dirty enough.
I have just installed this and slung my 24" on one side. New 27" from IT should be arriving tomorrow to go on the other side.
https://www.vonhaus.com/vh_en/home-office/double-arm-monitor-mount-with-clamp
Really impressed with the quality for the price.
For a single monitor at fixed standing height, you could probably use the below and take off one of the brackets
https://www.vonhaus.com/vh_en/home-office/vertical-double-monitor-mount
Or for double, a similar tactic with this
https://www.vonhaus.com/vh_en/home-office/quad-monitor-mount