When I was taking a few notes about Ashigaru, japanese foot soldiers of the jigoku-era, I found that most contemporary illustrations on this page stem from one and the same book by Utagawa Kuniyoshi.
The main source for the Wikipedia article, Stephen Turnbull, references in his Osprey works to a book called Zhôyô Monogatari and uses it as the source for quite some of his contemporary illustrations, that seems to have a very similar style to the works of Kuniyoshi.
Turnbull cites in the further reading in the Osprey Warrior #29 - Ashigaru, that his reearch is based on Yoshihiko Sasama's research that uses this Zhôyô Monogatari as one of the main sources. A search on Pinterest reveals quite a lot of pictures are contained in this elusive essay.
Using Google Translate to get monogatari in Kanji(物語) and the Japanese Wikipedia on Ashigaru, I was able to discern the original title to be "雑兵物語", but that is a redlink. Google helps though, that it is to be read as Zōhyō monogatari. Note that the Zōh/Zhô seem to make no difference for the pronunciation.
Now, I was wondering if this manual, the 雑兵物語, was ever translated as itself since my Japanese is pretty much not suitable to read it.