The Mecha Kha'Zix skin isn't currently included in any verified League of Legends account on BuyAccount. Stock rotates constantly — the moment a seller lists an account that includes this skin, it'll appear right here. Same URL, no waiting.
Not in stock right now. The page you're looking at is the permanent home for the Mecha Kha'Zix skin on BuyAccount — bookmark it and we'll surface listings here as soon as they're added.