I use the ones I had for my mustang. It's a 2 piece set and they are the spring open ones. They fold down to about an 8 inch circle. I bought them at WalMart for $10-15. But they aren't long enough for the whole windshield so i have to set them against that little ridge in the middle of the dash where the info display is.
They probably aren't as effective this way since there is some black dash visible to the sun, but it's sure better than nothing.