Just wondering?

Has anyone seen these before? Three sided Japanese motif. These can be used as a vase or a wall pocket as it has feet and two holes in the back. I am wondering how rare they are? The wall pockets/vases are marked with a sticker Japan and marked with a black number 4020 on bottom of vase/wall pocket. Therefore, I'm wondering just rare they are, as I have read they are, but I assume they were mass produced. Thanks so much. Have a beautiful day and happy treasure hunting.