I was just leafing through a catalogue for an upcoming R. Maresch & Son auction (they are a very upmarket philatelic auction house in Toronto) and came across this interesting essay from 1958.

It describes the item as a "native indian essay in black, deep green and red on buff, imperforate pair on gummed paper, n.h. left stamp with tiny gum wrinkles, right stamp very fine. Est. 250+"
Very cool, very '50s. Certainly wouldn't pass todays standards. But I like the way his war paint makes a 4 on his face, same as the denomination.