Toy Line: Super Ninja-kun (Super Ninja Boy)
Location:
Yahoo! Japan
Vendor: Greenbox987
Auction Number: f77004420
Collector's Note: The questionable Google translation indicates this may be from a line connected to a Famicom/NES game. In any case, it's a neato sculpt and a brilliant picture. Reminds me that I need to upgrade my own light box.
Update: Thanks to Jkaris for identifying the Famicom game this line is based off of. Furthermore, it seems as if the game is a follow-up to an earlier game based on a manga (and anime) of the same name called Ninja Hattori-kun; Hattori Hanzō of course being the most famous Japanese samurai/ninja of all time.
Update Update: Uh, so it's not Ninja Hattori-kun, it's just Ninja-kun. Still a Famicom game though! Thanks to @TxAxKxU for the assist! See the Ninja-kun Famicom game below. Note the ninja in the top right of the cartridge picture.
Credit: I Heart Famicom