I used to build model airplanes using a corrugated plastic. Once the wing got in pretty bad shape after a crash. I called around town to some sign companies. I found one that had a selection of various thicknesses of this plastic. I went to have a look and found the selection was like 1/16" to 3/8". Various thickness's and various colors. It's easy to cut using scissors. The thicker I used a exacto knife.

Might be worth a try. The thicker has more resistance to any crushing.