There are split rims, split rings and in your case, you have the removable ring type rim.
The rims were designed to be use with inner tubes.
This type rim can be very hard to find in good condition.
Good alignment and fit (ring to rim) is required. If not correct, the ring could pop off and cause serious damage.
Warped, dented and heavily rusted parts should be avoided.
Many tire shops will not touch this wheel because of split rim phobia.
You may have to take it to a shop that does big truck tires.
The hubcap on the front looks like a 1/2 ton.
You will need the deeper 3/4 ton caps for the rear.
You can purchase the clips, that hold the hubcap, separately.
Tires:
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=788072
