The Decktet is available in a free print&play version which you can make yourself, and there are also pretty sets available to buy from a number of vendors.
Print your own
From DriveThru Cards
The cards from DriveThru Cards are printed on premium black core card stock from French paper manufacturer Arjo-Wiggins.
The Double Decktet: Two copies of the Decktet, which you can use separately or together. One copy is the classic Decktet. The other copy is all-new the capital Decktet, which has cards with all the same suits but with brand new art and themes. $17.99
The Decktet: A single deck with the firmament card back. $9.99
Дектет: A single deck with card text in Russian. Either because you because the Cyrillic alphabet is familiar to you (so it's comfortable) or because it is not (so it's exotic). In either case, it makes a great double deck along with the usual English version. $9.99The Deco Decktet: An iconoclastic alternative with all of the same structure but none of the pictorial content. Pretty shapes replace depictions of fantasy people. $9.99
DriveThru prints the cards on premium stock. They look and feel great.
From The Game Crafter
A single deck is a complete Decktet plus several information cards, available with one of two different card backs. $9.99
Suit chips: 72 chips, 12 of each. The 32mm wood-filled plastic chips come in six colours. The stickers come on a sheet, and you apply them yourself. Not a complete game; you also need a copy of the Decktet. $17.99
The colour and print quality of these decks is nice, and they come with rules and reference cards. But really the reason to order from them is because you are also getting chips.
For more information on the card backs, see the card back gallery.