I wrote a simple shell script[0] to scrape and output the latest image.
It uses the tiles from their online satellite map[1], and can output images in increments of 1x1, 2x2, 4x4, 16x16 tiles (each tile being 550px by 550px). Here is an example with 2x2 [2]
If you have any suggestions or bugfixes, feel free to fork or comment.
EDIT: Also works for a single tile[3], also clarity.
[0] https://gist.github.com/Syrup-tan/1833ba1671c7017f0d59
[1] http://himawari8.nict.go.jp/