If it is out of stock in Japan, I wouldn't rush out to buy it right away. I'd let the dust settle down first.
The Japs usually keep the best for themselves, and normally ship their 'seconds' for overseas consumption (especially when demand is high). I went through five samples of the 80-200 AFS one time (when it was just released) and all were marred in one way or another with a manufacturing flaw (mostly bubbles and large pieces of black flocking paint chips on the elements). Flaws I don't even find in used equipment. For a $2.4K lens, it was unforgivable.