I'm not sure where people get the idea that fakes don't come from Japan. They do, in large quantities, same way there are fakes in the US. Japan has pretty strict laws against counterfeiting, but they are not designed to protect buyers abroad. If you look at all the fine print on Buyee, they state that they make no assurances of authenticity. They have nothing to do with the sellers. Buyee is just a go between that buys items from sellers for you and handles getting it to you. But they don't stand behind the products, and they won't intercede on your behalf with the seller if they ship you a fake. You have no recourse for purchases on Buyee, other than perhaps with your credit card company. But that can put you at odds with Buyee and affect their willingness to serve as a proxy purchaser for you.
There are tons of fakes on Buyee. Caveat emptor.