If you use 22.5” tires(a good idea), it will probably break your budget since wheels will also be required. But it will add to the value of your truck. Perhaps you could start looking for wheels and a good buy on 9 x 22.5 tires and do one pair at a time.
Ed
His picture shows a 9x22.5 tire mounted on a rim so I think he already has what he needs. I think he wrote 20 inch by accident.