[Daldaen]

http://tancidtherogue.com/ragebringer.html

The Vial of Swirling Smoke, which instantly casts Gate on you, can be purchased at vendors in many of the main starting cities (Ak'Anon, Felwithe, Greater Faydark, Kaladim South, Neriak Commons, Neriak Foreign Quarter, Plane of Tranquility, Qeynos South, Rivervale, Shar Vahl). All the merchants who sell it have a limited supply -- once they are you, they are out until the server restarts or until you kill them.

I think it's just 1 potion per vendor. Is it worth logging into live to check some vendors?