Olivér's Stickers is an online shop specialising in replacement stickers and in sticker mods, and is renowned for durable and high-quality stickers.
It has now branched out into selling assembled and tested versions of Grégoire Pfennig's designs, including the 33x33x33 if you have €15,200 to spare, and Twisty Tex's puzzles.
It does not sell twisty puzzles generally, but partners with and links to the HK Now Store where you can buy puzzles.