I think this is the third time I have heard that stationary idea, so there definitely could be something to it.
I think something as simple just monthly 3-4 novelty erasers would sell really well.
I also recall reading that paper yearly planners are popular in Japan right now.
Edit: I was thinking of these http://matome.naver.jp/odai/2135267959864327501 -- http://www.1101.com/store/techo/2014/planner/