Thomann is Europe's largest online music store. I guess they normally don't deliver to the US, but it's worth trying. Did you check the specs about voltage?
[Edit:] Gary was quicker regarding voltage...
BTW, I'm just coming from a band rehearsal, in which we also tested various of my speaker systems, mainly the HK Lucas Nano 300 and the db technologies K300, which I bought recently. They are small and a pair weighs no more than the Nano 300: 11 kilograms.
I had to play 'against' a drummer with these. At first we just used the Nano 300. Everyone was amazed how much power it had. No problem playing with the drummer (I play left hand bass and various sounds with the right hand). the singer also used the Nano 300 input.
Then, I switched to the pair of db K300 speakers. We were all absolutely thrilled by them!!! They don't have any deep bass of course, but otherwise sounds like piano, e-piano or brass sound spectacular with them, very loud and very clear. Apart from the subwoofer bass, they beat the Nano 300 by far.
Then we used db K300 and Nano300 in combination. Absolutely fantastic. The great, great clear mids and highs of the K300 and the subwoofer of the Nano 300 were a dream team.
So, if you don't need an extreme amount of bass, I would surely prefer this combination to one Lucas Nano 600.
Link to the db K300:
http://www.thomann.de/gb/db_technologies_k_300.htm