The "AppleDesign Powered Speakers II" uses a standard (12v/1A/positive polarity) AC adapter. These speakers do not have a power switch so I leave them unplugged when not in use. Not sure if they'd be easier to find or not.
 
Btw, I came across this while looking for a picture of the v2 speakers: http://us.ebid.net/for-sale/apple-design-powered-speakers-model-m6082-audio-cable-139135722.htm
 
For the sake of reference, here's the back of the "AppleDesign Powered Speakers": (Courtesy of ramdom image search.)