This is a postcard of a 13th wooden statue of a Zen Buddhist priest, from the Japanese Kamakura period, an era which I know nothing about. In fact my knowledge of Japanese art & culture is not great, period, but I can appreciate what is obviously a beautiful work of art.
This card was published by the Pennsylvania Museum & School of Industrial Art, and I assume it was originally sold in a gift shop.
I don't know the age of the postcard, but I suspect it is Pre-WWII. It is divided back, and there's no real clue from the stamp box.
I like art cards.