The Warden Scout's Gloves are part of the Regalia of Weisshaupt (rogue) armor set.
Acquisition
Acquired in the "Sarcophagus room" located in Corypheus's Prison - Tower Base. If Hawke lights all six torches in the Sarcophagus room, the Sarcophagus is activated and the Warden Scout's Gloves may be looted from it. Armour stats are determined by the level (or Act) you do the quest.