Havel is a merchant selling mid level armor in Val Royeaux in the Summer Bazaar. The store itself becomes available after the war table operation Address the Chantry in Val Royeaux during the main quest The Threat Remains. To access Havel's store, either In Hushed Whispers or Champions of the Just needs to be completed first. He is located in the same store as the expensive merchant and weapons and upgrades merchant.