cherry blossom or plum blossoms on celadon green, large ceramic wall pocket vase

Lovely celadon green ceramic wall pocket with flowering cherries or plum blossom design, hand-painted under glaze. This isn't marked at all that we could find, possibly vintage Japan? It doesn't really look like Chinese porcelain to us.

The wall pocket measures 8 1/2" long, and is in very nice condition without chips or damage.