What wallmount for a 50inch tcl qm8b?

Hi there. I looked around and apparently this tv

https://amzn.eu/d/gikJlCR

Needs a 800 x 400 vesa wallmount... I can barely find any, it's not like the tv is huge, so is there a solid wall mount for this that can be moved to the left and right? And is that vesa listing even correct? I found a different one saying 400x300...

Thanks!