Originally Posted by CrimsonEclipse

http://www.rvtoyoutlet.com/p-RV8612.html

This one is a good solution for the price. I would like one similar but turned 90 degrees so the longest dimension is vertical. Also a draw string on the top with a flap would help minimize the movement while in motion and the flap would cover any part that sticks out.

(If I only had access to a heavy duty sewing machine)