[other nice pics here]
The love of post-war design in Japan isn't only for Eames chairs and the homegrown 60's Danish knockoffs. There's also the simple, rustic, functional furniture that had to be made locally from whatever wood was available because, well, someone--not pointing any fingers here, Major Gruver-san, just sayin'--someone bombed the country's industrial and urban infrastructure to smithereens, and kindergarten furniture factories were not high on the Occupation Force's reconstruction priority list.
From their design similarities and the nostalgic recollections I've found, it seems these postwar youchi-en chairs followed a central or common model. [That white one was found in Meguro in central Tokyo.] Metal chairs start turning up around 1960. [Though the chairs are from all over, most of the pics are tiny, webphone-sized. The big shots come from Legendary Home, the not-to-be-missed blog of Kato-chan, a decorator on Tokyo's commuting fringes who could be the Japanese love child of Peter Mayle and Carson Kressley. Dude drives a Citroen.]
The chairs hit the sweet spot of recent resurgence of old-school Japanese craft and traditions, as well as the simple, handmade, natural thing that's so hot with the kids these days. Which means modern interpretations and reproductions are available, like this stackable adaptation from the workshop/shop, Donkoubou: