From our very own Tech Tips:http://www.stovebolt.com/techtips/wheels/
Some folks also use a certain 16" (or is it 16.5"?) trailer wheel, they should be along to comment shortly, or you could do a search, as it has been discussed before. ...single wheels only...
Personally I like the 19.5" wheels best for the 1 ton.
Wait a minute.... do you have single or dual wheels???
If dual then 19.5" may be the only option that fits over the drums?
Also, the "split rims" you mention may be perfectly acceptable, as there are only a few of the multi piece rims that are now considered unsafe, to bad they give the rest of the multi piece wheels a bad name... Read about it in the same Tech Tip.