Wave 2 Power Battlers found in America. Only Scorn and Drft, so maybe Optimus was either already sold, or it is in a revision wave (as wave 2 has those three listed).

Store exclusive Construct-Bots Silver Knight Optimus and Grimlock have also been found at a Target in America for US$15. (Optimus is just a Dinobot Rider, not the Warrior class)