This dropped for me on 12-14-08 from "a rotting corpse," which is one of the undead mobs on the 3rd floor, in the large room leading to the throne room (not the room where Charbones spawns)...[link=http://eqbeastiary.allakhazam.com/search.shtml?id=22627]
Drops from the Nokk and zombies in the far north of the Hollows in Crescent Reach, northeast of the river, along with the plate and leather equivalents. I have not seen the silk drop yet, though.