ケールの生葉 or ケール生葉
生葉 is essentially fresh or raw leaves.
Though you can search online for various places to order kale from, here are a few I found (note that some may not be currently shipping kale due to the season):
Ryokuoukan Net Store (緑王館ネットストア) - They don't use pesticides.
Tohoku Bokujo (東北牧場) - They don't use pesticides. Says kale is only available in early summer and fall though.
Masuda Online Shop (マスダオンラインショープ)
Tokai Aojiru - They sell fresh kale leaves, powdered and frozen aojiru; they also don't use pesticides.
Gotta be honest, I can't wait to order some fresh kale and make me some kale chips!