You might do better outside Japan. I can get Yamazaki 18 for $249.95 at my liquor store in Portland. They also carry Yamazaki 12 and Hakushu 12, but less compellingly priced at $84.95.

Spent the last few days in Tokyo -- relatively limited stock available with age statements, and nothing at bargain prices. Among the places I visited, I'd say urban Kyushu had the best supply and prices.