Consumers in Japan can only choose between two Wii U system options in Japan at present. There’s the original 8GB console released back in 2012, and the 32GB Wii Sports Club bundle featuring tennis, bowling, and golf.
Nintendo’s website confirms that all other Wii U consoles are no longer available in Japan, including the Dragon Quest X and Monster Hunter 3 Ultimate packages, and the black/white Instant Play Family Sets.
Reader Marquis Ozu tells us that black Wii U systems as a whole are pretty much gone from all stores in Japan, which is understandable based on what Nintendo’s page has listed. Retailers like Sofmap and Bic Camera are no longer carrying the color variation, and that’s probably the case with all other locations.