There are some exceptions, but most abjurations only drop off a single mob. Off the top of my head, I can think of A body, A hands, and A feet dropping off of 2 different mobs. Most other abjurations only drop from one thing.
There is a slight possibility these might drop from Einherjar, but I have yet to see proof of this yet beyond speculation. I know that Einherjar drops a few misc abjurations, but for the sake of Sky and HNM discussion I'll just ignore that.
These drop off Kirin with what my linkshell has found to be about a 10% droprate over the course of over two years.
Good luck, and happy hunting. ^^