Hi Mike,
Herping is huge in Japan. See list of shops here:

http://a.hatena.ne.jp/kindgecko/simple

Dizzypoint Tokyo has nice pairs of Spencers, Parenties and Lace Monitors. Rainforest, endless zone and Maniac are good shops - they can send what you want by post.

Aomori - plenty of helps there. Tokyo is the place for shops though.

Best, Jules