I don't know the Chinese brands, but in Japan Shiseido would be a good option for higher-end department-store type shampoos, and Kanebo seems really popular for more of an everyday drugstore-type brand (I can usually find a couple of different "flavors" of Kanebo Naive on the shelves at the bigger Asian markets in the region, and if it's popular enough that folks are demanding it in exports you know it's got to be a big thing.)

And judging by this post (http://smt.blogs.com/mari_diary/2005/07/asian_conscious.html), it looks like some of the big Western brands like Pantene are also readily available in the Japanese market. So, considering that Gojyo smokes Japanese Hi-Lites and Sanzo smokes American Marlboro reds (*shudder*), if you really want to have the boy using some particular brand, you can probably handwave it if it's something from a reasonably big company. :)