I could swear I saw 2 different styles at my dealer one day on new units....one looked like the standard protector but one looked much wider (and uglier). I want to make sure I get the standard one that looks like this....
There are several. This is the one you want. I ordered this from the Priuschat shop, and it's exactly as pictured. Very nice, and easy to install yourself. PriusChat Shop : 2010 Toyota Prius OEM Rear Bumper Protector [2010BP] - $41.99 Don't know the Toyota part number, if you want to get it from a dealer...
The first one (the red car) is the official Toyota rear bumper protector. The second one (silver) is probably a regional thing (i.e. it's probably Gulf Toyota's rendition of a bumper protector that the rest of the country doesn't get)