You can find good seats in wrecked cars. I got nice gray passenger seat out of a 2006 Volkswagon Passat for $40. It has full manual controls, reclines, raises/lowers with lumbar support and has a good set of slides on it. I've found mine very comfortable. You just need a torx bit the right size to pull it out of a wrecked car. it weighs 45lbs with sliders which is a reasonable weight.
Personally I don't see the point in a high back chair for a sim racer. It's not like you have to worry about whiplash. That added height is purely ornamental. Since I play in VR I don't want anything I could hit my headset on while looking into a corner.
Anyway, it's just another option.