Travelmore
Adventurer
Thought there might be some interest in this article. Unfortunately it lacks good detail of why they are banned. There are some other interesting cars and potential expedition vehicles as well.
http://www.wired.com/autopia/2011/04/cars-uncle-sam-says-you-cant-have/?pid=801&viewall=true
http://www.wired.com/autopia/2011/04/cars-uncle-sam-says-you-cant-have/?pid=801&viewall=true