Hi RiverRat! I went to the OC Prius Club meeting and they raffled one off.. its actually pretty cool because most of the ones I've seen online were cloth.. and I guess someone that makes them finally switched to a hard plastic (pretty nifty looking).
Here is a link for one of the people selling the cloth ones.. I'm not sure if she's the same person that sells the hard-plastic one.
Try taping a cardboard shade temporarilly. It's really not the solution. I threw the one I purchased on "E" bay away!
And that problem isn't just in California, I hear the Eskimo owners have trouble seeing the thing also for several months of the year.