LOL, no problem Kev,
There are indeed no power laws for them, so the quakenbush 50 caliber and similar http://www.quackenbushairguns.com/airgunelka.html are perfectly legal, but just not deemed powerfull enough to kill squirels or rats.
Just in case anyone is thinking of making the trip there are however many laws governing airguns, like no one under 18 may purchase them and a bunch of other draconian over enthusiastic ideas by people with nothing better to do than legislate , but thats another matter...
tim