He didn't even have to buy a wig.
In a good prank, your victims either scream "Oh my God!" or they spontaneously laugh. (And then they throw your wig at you.)
Josh update his video. Go here for the new version>>
Wig from my own hair prank
Found thanks to Art of the Prank>>
Wig ad is from a 1970 ad for "great wig buys" at Found in Mom's Basement>>