^ But even 50k-100k per release is still estimating way too much. Just look at the current sales for Korea in the year 2009 (who after Japan is generally considered to have the best music sales in asia):
http://www.soompi.com/forums/index.php?showtopic=317370
Sorry, don't mean to jump on your post.
But it seems that people here are always over estimating Ayu's sales in other asian countries. She definitely is one of the better selling Japanese acts outside of Japan, but that doesn't necessarily mean that the sales are actually high.