As a player this set is really underwhelming, so I’m not buying a box of it in English. I do, however, love the cards in it and would like to buy some Japanese boxes of it. Since I very rarely buy Japanese boxes, I was curious as to where the go-to place/person was to get them. Thanks in advance.
I always go with AmiAmi. Their prices are the best you will find, the only problem is that everyone knows it, so the boxes sell out fast. I’m not sure if they’re in stock now. If you want them fast and don’t want to wait, I’d go with tokyo-hobby on eBay. The prices are reasonable enough and shipping is reasonable as well.
AmiAmi is down right now, just looked at Tokyo-hobby’s prices and they seem really good, thanks for the info.
In the future if you are wanting to get Japanese sets, like @fourthstartcg said, AmiAmi is the best place to order. Since they are a wholesale company, they can sell for cheaper than retail on the preorders. 
Hope this helps! Good luck collecting this set!
I can’t wait for my boxes 
I’ve had great dealings with tokyo hobby, even before they changed 