How to find these dealers on Yahoo Japan?

So, I was looking through Danny Choo's posts for more news on robot Mirai, when I stumbled across this:

 

http://www.dannychoo.com/en/post/26989/I+Doll+38+Dealer+s+Booth.html

 

Waaah, it is terrible for my wallet, but I want half the things shown here for my sweet little Rika. But I kind of don't know how to search for these dealers. I am especially interested in the masks shown at the bottom from ALBA DOLL. I see that some names have characters next to them that are easy to use as search terms, but I am not getting any luck. I guess I am still too green with Y!Japan to get any good search results. Could I get suggestions on how to find these items? Are any of them super hard to get outside Japan?

 

Thanks!

The thing is, some of those dealers are only selling their items on conventions. They are usually what can be called a "circle" or "Doujin Circle". Circles often consist of hobbyists and are not a "real" company(someone else may explain better how circles works). Out of Base are such an example, even though they are selling some of the heads on the web too. Chances could be that you have to find someone who is selling their masks second-hand or get someone to visit these events and buy one for you. There's no guarantee that they have a YJA account.

Ahh, I was afraid of that! Thanks so much!