They got rid of this, I went to get one and found the post office had been changed, it happened a while back, I think the last two coins, so 2008 and 2007 I got from the mint. Did see a few coin sets for sale in Preston WHSmiths though, but never seen them anywhere else.
Basically I think you can really only get them from the mint, or through dealers, not sure if this is a money making ploy.