I don't know about the concealer, but if you live close to the Radisson mart (it's now called the Sheraton mart) that is really popular, they sell it in a store on the first floor on the right hand side. That's once you check in/sign it, not the open stores. I don't have a name for you because you know the stores in the Sheraton are not namebrand. It is to the right of the elevator (the ONLY elevator lol). I know it sounds like I'm being vague, but the Sheraton is relatively small. Hope that helps!
EDIT: Forgot to mention that the NYX stand can be found at the back of the store. They have a bunch of stuff!