Interesting, didn't know two of the manufacturers yet.
Warcrow has some samurai/ japan style stuff:
And soon Wargames Factory will have:
If you look here, even if it is german, you can figure out the name of some more manufacturers offering Samurai:
(Darksword, Fenryll, Hazgaard Editions, Silver Fox Productions Inc., Tales of War, Westwind Productions, Wyrd, Micro Art Studio (for bitz))
Edit: the last link didn't save my search word. Just type in "Samurai" and klick on "Suche starten"