Where to buy an Asus Strix G16 with upgraded storage already?

I live in Fukuoka and I'm planning to buy an Asus strix g16. But I want to buy it with at least 2 tb or 4tb storage already installed. What store in japan/Fukuoka will let me do this. I don't mind buying it physically or buying it online. But Amazon or BIC or Asus Japan website won't let me choose a laptop configuration with 2tb or 4tb