Powerpop is very big in Japan at the moment. The Rubinoos recently played here. I've seen the Fast Cars, the Boys and Nikki Corvette in recent times. And in fact I'm going to see Paul Collins live in Tokyo tonite! There's also a powerpop revival happening in Tokyo spearheaded by bands like Firestarter, The Raydios and the Tweezers (all with former members of Teengenerate).
Some powerpop 45s I've recently found include the Troops (from Australia), the Boyfriends (the '78 UK band not the indie rock band) & The Features (again not the indie rock band), and how about the Cigarettes?