Hi there, Caroline,
Mini blinds, properly sized, will work well in your trailer (especially on the rear window and center portion of the front window).
If you go with blinds for the front window, you'll prob. want curtains to (at least) cover the the curved end sections of the front window.
For use in a travel trailer, may I suggest aluminum or light-weight metal mini blinds? They can cost only slightly more than vinyl ones and are available at most Lowes, Menards, Home Depot, etc.
The reason I recommend these is because they won't sag (distort) as the plastic ones sometimes do. Heat can really build-up inside an Airstream, especially when it is closed up during the hot summer days. This heat can temporairly soften the vinyl blind slats and leave them 'saggy'.
Enjoy using your creativity in renovating your Caravel
P.S. I like your choice of Airstream model to make your own!