Hello Tom
Your journey looks to be an amazing one! Have you checked out the hennessy hammock? I've never used one personally, but my father says they're great because you can easily tie them to just about anything from trees and rocks to road signs and cars. They also have a rain cover and insulation system to make them a little bit more livable in crazier weather. Might be worth looking into.
Have a great journey!
Here's a link to the hammocks:
http://www.hennessyhammock.com/