The Dragonbane Cuirass, like most non-set unique armor in the Divinity II: Flames of Vengeance expansion, is available for purchase by anyone with enough coin. The cuirass is sold by Gofannon, the armorer and merchant located south of the Ministry in the Great Market district of Aleroth.

Cost: 58400 gold
Discounted Cost (mindread Gofannon): 43800 gold