But is it the real deal 100% original Mac version released directly by Apple? The ones you linked look like third-party.
Try this site:
http://www.idownloadblog.com/2013/09/11/new-ios-7-wallpapers/
You'll have to scroll down through quite a few other wallpapers but it's on there.
How did he get those wallpapers? (I assume they are originals? Are they?)
There is a problem, the resolution and aspect ratio of the wallpapers are set for the iPhone. The iPad version should have more horizontal pixels since it has a higher resolution.