The coaster brake is actually a specific type of wheel hub that allows freewheeling and braking. What you linked to was not that. You'll want something like this...
http://www.velomine.com/index.php?ma...efuvokqr329d80
It says the set on there is sold out (hence my link to a single rear wheel). I'm sure you can contact them for more info, or find a similar product elsewhere.