https://www.staples.com/beautyrest-platinum-sofil-bonded-leather-executive-chair-black-49404b/product_24381184
Best chair I've ever owned. You can probably find it for cheaper than $300 if you do some searching. It's available at Costco and Staples that I've seen in stores.
But as for your back pain from working/gaming at a desk, there are certainly other things you can do. I'm an occupational therapist; I've done a lot of research and education in ergonomics if you'd like further help with your desk set-up, lmk.
Virtue -
"You don't need a reason to
Boko United
."