just buy it and open the box when it gets there. no issues the few times i have ordered stuff from japan and overseas to the US.
the only issues to be aware of are voltage, warranty and service.
my 100 Watt japan luxman CD player requires a voltage transformer to use it with US outlets. not a big deal for low wattage sources but good ones are needed for amplifiers and they can be large and heavy.
warranty is good but i am required to send it to japan for servicing. luxman USA will not service 100 volt products.