I just tried the new Google image search (where you can drag an image into the Google search bar ... from your PC!). And, I found this image at this site. You can't get full iPad 1024x1024 size, but you can get it 999x999 (just fill in the numbers at the bottom).
Thanks for this. I completely forgot about the google image search trick!
However, when I try 999 x 999 and then try to save, it won't save but I can save all the other sizes listed.