Now that the product has actually shipped...we know the exact numbers ;-)
With your original purchase of "Contact" w/free flat pack shipping, you'll receive 28 cards (28 performances).
Refills are available in a "3 pack saver" for $39.95. You'll get 3 decks (56 cards per deck)for that price.
Word is that a single deck option may become available...you'll have to contact PM directly for the release date.