Rarity in her G3 colors. Close enough anyways. And if I were more accurate, she wouldn't have a cutie mark from this angle but since G4 has them on both sides, I included it here.
Though whether or not it's facing the right direction can be argued. Sometimes the animators in Friendship is Magic flip the cutie marks and sometimes they don't.
My Little Pony, Friendship is Magic, and all related characters © Hasbro