I consider all of these and other Korean ones as custom boards. They have super limited runs and they might as well be one off as far as I am concerned in obtaining one. I have read the other thread about the reasons why there are so few, and I get they have space concerns and so on, but... there are ways. I mean sh!t I live in a 200sq ft apartment, and I would have no problem organizing and distributing a big keyboard buy if it was necessary. It's what relatives garages and whatever are for right? Store 30 here, 30 there until you can get them shipped out. It's not that complex and you can have bigger buys for lower prices. I wouldn't want to do it on a regular basis, but I mean really, not that bad to do once a year or something if you really wanted to.
Also I will assume that in a smaller country like S.Korea, a good deal of the active members live in one of the larger cities like Seoul, so they could easily spread out the burden. Sorry, but I am calling cop out on that excuse. I still feel they do it for an 'elite' status.