Are you looking for a crawler type of chassis or a monster truck type chassis? New era models used to make a good looking monster truck type for the clod, but aren't anymore.
If you knew how to braze or weld, you could build your own chassis.
http://www.rccrawler.com/forum/newbi...ube-frame.html
While it's not a tube chassis, you could get a chassis for a TXT-1 and fit the clod axles to it. It's a good looking chassis that's plenty strong and it's designed for cantilever suspension to boot.
http://rcmtraracing.4rumer.com/t7-zombie-destroyer