I've been looking for the best/cheapest option to import one myself.
There are several retailers you can use that seem reputable to import one to the US
Play-asia (expensive, but reliable it seems)
Nippon-Yasan (cheaper, but can be slow by some user's comments)
Eurotaku (haven't seen much on them, but are about the same price to import as nippon-yasan)
Amazon JP, with tenso as package forwarder (Might be cheapest option overall, but tenso requires you submit ID to verify address so that may hold things up a bit)
Amazon US (Prices are a bit high, but you can use amazon credit if you have it and amazon is typically pretty good with handling issues. Probably $20-40 higher than nippon-yasan and it still ships from Japanese seller anyways)