Hello,  To the gentleman in Japan who is looking for a source of dry
hide glue, Stewmac seems to stock many instrument-making supplies
including hide glue flakes; see

http://www.stewmac.com/shop/Glues,_adhesives/Wood_glue/Behlen_Ground_Hide_Glue.html 

What it might cost to send it to Japan, I can't say.  A friend of mine,
a fine-furniture maker, points out that there are as many forms of hide
glue as there are hides.  For example, hide glue made from rabbit skin
is known for its flexibility.  I can inquire of him where these other
sorts of rendered skins might be available if there is interest.

Harry Norris