Probably a long shot, But check into the insurance agencies on the Mexico border... They may have some information on how non U.S. citizens can aquire insurance.

Hope they are helpful!

 

Hello Giles!
Thank you for your posting. Just the way I feel, and experience this.
We have verified with the rental company that we can rent the Jeeps, I just am a cautious type and would feel better if I had an insurance policy.
We are experienced off road drivers, so I hope this turns out well. We have signed up for 5-6 level of trials.

Tor