Leggings of the Plague Hunter

The Leggings of the Plague Hunter is a quest reward from the Argent Dawn faction.

Source
The quests are given by Quartermaster Miranda Breechlock. She has a Quest for each tier of faction (Friendly, Honored, Revered and Exalted). It requires a turn-in of a large number of Insignia of the Dawn and Crusade. (See Armaments of the Dawn for summary). The Quests are:
 * Superior Armaments of Battle - Friendly with Argent Dawn - 30 Insignia of the Dawn and 30 Insignia of the Crusade
 * Superior Armaments of Battle - Honored with Argent Dawn - 20 Insignia of the Dawn and 20 Insignia of the Crusade
 * Superior Armaments of Battle - Revered with Argent Dawn - 7 Insignia of the Dawn and 7 Insignia of the Crusade
 * Superior Armaments of Battle - Exalted with Argent Dawn - 6 Insignia of the Dawn and 6 Insignia of the Crusade

Other quest rewards are:
 * Band of Resolution
 * Verimonde's Last Resort
 * Supply Bag
 * Band of Piety
 * Sanctified Leather Helm