Because Achilles armor has been taken by someone else, where does he get new armor to face the Trojans?

Thetis implores Hephaestus’s to make Achilles a a "killer" set of armour. Hephaestus afrees and forges a breastplate, a helmet, and an ornate shield with the images of constellations, parstoral nature, dancing children, and cities full of men.