https://www.steelcase.com/products/office-chairs/leap/
I have an older version. I found them at a place that sells office 2nd hand office furniture. I got a GREAT deal. I was able to get a tall piston for one of them to accommodate my architect desk. You will find these office furniture resellers in almost every city. Check local and find something dope.
The place I went hires people who are rehabilitating. Felt good supporting them.
HumanScale chairs are pretty fantastic as well last time I checked. Herman Miller makes one that’s really amazing if your not a giant. It’s a step up from the aeron. I feel the Aeron is a bit over rated.