The only shop I've
ever seen with either of those in stock is Mandarake, and since you have to search for Umineko in Japanese characters to find either of them I'll go ahead and give you the
search link 
. They should both be on the first page.
(...which reminds me that I really do need to get to ordering that motion graphic...*bookmarks*)
EDIT: They appear to be sold out of Musicbox BLUE - I'm not sure if they'll be getting any back in. But I thought I'd show the out of stock items too just so you have the links and you can keep checking back.