Check out crandall office too. They buy used chairs (10+ years old), clean and refurbish them to mend the foam and replace all the upholstery. Each chair is then warrantied for another 12 years through them.
You can probably get Steelcase chairs cheaper on craigslist/fb marketplace/furniture liquidators, but remember that they will need to be cleaned.
If you go marketplace route, don't discount the steelcase drive. It's now discontinued, but I've done my entire PhD in that chair. It has been in use since 2002 and aside from fabric rips, there's no problem with it. The rest of the floor is outfitted with them and are no worse for wear after 20+ years. You can maybe find this for $10-$120 used, but know that there is limited options for parts replacement. If I could have found one, I would have used it for my home office.
For modern chairs from Steelcase, my recommendation is the Amia chair (not air) which has good structural integrity, modest height but not intensity lumbar support, and adjustable recline tension. The leap is a very common recommendation, but tends to have a stiffer seat, more adjustable lumbar support, and a bit more available angle of recline. I'd avoid the Gesture, series 1, series 2, or other models from Steelcase, but YMMV.
At crandall or BTOD, you're likely to pay 4-600ish for a refurbished Amia. If you buy online, only buy from these two. Madison Office Furniture looks cheap, but their "Open Box" deal is referring to the fact that the chair/parts making the chair have been out of a box before. Typically for 10+ years... The misleading representation should tell you all you need to know on them.