Any tire dealer should be able to order a 9:00-20 NDCC (Non Directional Cross Country, sometimes called NDT, Non Directional Tread - The "Zipper" tires on your truck) tire for you. If you can't find used tires anyplace, find a tire dealer who also does large truck tires, order the tire there and have them mount it as well. It should cost $100-$125 for the tire and around $25 to mount it. Any more than that and find another dealer.
Don't even think about trying to mount the tire yourself. You don't have enough knowledge or experience to do it safely. These tires are deadly if not mounted properly. How do I know? I used to be a paramedic, I had to pick up a guy who killed himself while inflating a tire he had not mounted properly. I also picked up two guys who killed themselves because they thought they didn't need a jackstand, but that's another story.
Welcome to the group. There is a lot to learn about MVs, search and read our forums, you will find most any topic you can think of covered here someplace. Good luck in your new hobby!
Don't even think about trying to mount the tire yourself. You don't have enough knowledge or experience to do it safely. These tires are deadly if not mounted properly. How do I know? I used to be a paramedic, I had to pick up a guy who killed himself while inflating a tire he had not mounted properly. I also picked up two guys who killed themselves because they thought they didn't need a jackstand, but that's another story.
Welcome to the group. There is a lot to learn about MVs, search and read our forums, you will find most any topic you can think of covered here someplace. Good luck in your new hobby!