Located in the basement of a ruined house southeast of Red Rock Canyon, close to the Spring Mt. Ranch State Park, along with a single Khan as a guard, the armorer serves her tribe by managing their supply of weapons and ammo. With an Acceptedreputation with the Khans, she'll even sell her wares to outsiders.
This same difference in vendor inventory lists also means that the Great Khan armorer will sell very high amounts of most ammunition, up to several thousand rounds depending on the type. Although these are very high amounts, they will be only half of what Quartermaster Bardon will stock on average.
This expansive stock of ammunition, weapons and armor, coupled with the 1:1 trades offered with a Great Khans Accepted reputation, allows for one of the only methods to exchange the Sierra Madregold bars for their full value.
She will not become hostile if the Courier is wearing NCR armor. The same also applies if Boone is in their company. She won't have any dialogue including to open her store, however, so removing faction armor is still critical.