No. Game items can only be purchased from inside the game. Therefore, if any other website or individual tries to sell you something outside the game, it is likely a scam or against the Terms of Service which could result in a suspension or ban of your account.
If you find someone or a website trying to sell in-game items or content, please Contact Us.
Important: The only exception to the above is official Sky merchandise from thatskyshop.com, which can include STAR features that affect gameplay.