To add some details to truckdog's post,
Any wheel with 10 lugs on 7.25" center hole will be hub piloted.
Yours should have a 4.75" center hole, and any tubeless wheels you find will have 5.25" center hole. Because the wheels are hub piloted you must have bushings made to take up the difference between larger center hole and the smaller hub. Some more info and details available here
http://www.stovebolt.com/techtips/wheels/Rim width, if you find some 22.5" wheels with the 7.25" bolt circle they will be 5.25" wide. Most tire manufacturers recommend a 6" wide rim as a minimum for 9R22.5 tires. I have 9R22.5 tires on 5.25x22.5 wheels on my truck, they were easy to install and seem to have sufficient space between the duals, again this is not recommended, but you can probably get away with it.
Other tubeless option is 19.5" wheels, they are very easy to find because they used them well into the 90's. 8r19.5 tires are about as tall and narrow as you can get for them, and are only about 32-33" tall, this may work OK on your older truck. I think they look to small on a 48 and later 1.5 or 2 ton.
Now the big catch with these wheels is they might not fit over your rear brake drums, a test fit is in order before you buy any.
Grigg
