I don't know what chair you should get, however I recently replaced my office chair and all I can say is if you spend any significant amount of time sitting at the desk get a mesh chair. OMG changed my life! It's like having cooled seats. I just got a cheapo one from staples. I think its this one, however was much cheaper at the time.
https://www.staples.com/Staples-Hyke...xoCLOIQAvD_BwE