About the only one I can think of off the top of my head is the Revell Ford F-350 PU, as it was a dually. I believe it is OOP now, but should be able to find it no problem on Ebay.
I believe I saw an aftermarket resin guy making some dual wheels as well as other big truck parts like rear ends etc. Sorry, I forget the name of it. Ask this question in the truck section of Model Cars Magazine forum and you are sure to get an answer.