According to the page (after being translated in Chrome) you can buy 2,3+ for additional discounts. No grayed-out button and you can add it to card. I'm gonna start saving up money and if it doesn't show up stateside before I have my PCS to the states I'll scoop one up and TMO it.
(PCS=Permanent...
I'm looking at purchasing a Sharp PN-K321 in Japan, since I'm stationed in Okinawa. I would need a step-down transformer for on base and in the states but I would be able to get the monitor for 373,200 yen which is short of 4000 dollars. Pretty good deal considering it's supposed to go for 5500...