seal box
A box for storing a personal seal (hanko). Rare term; most speakers would simply say 印鑑ケース or describe it as はんこを入れる箱.
古い道具屋で、小さな判箱を見つけた。
I found a small seal box at an old tool shop.
Compound of 判 (han, 'seal') and 箱 (hako, 'box'), with rendaku voicing of 箱 to ばこ. The exact historical derivation is uncertain, but the word follows a common pattern for naming containers.