Yes, you'll likely need refills after your initial 28 cards are used.
Yes, refills are available in a "3 pack saver" for $39.95.
(56 cards/deck x 3ea = 168 performances).
Per PM...supply is limited.
Also, careful not to 'double post' your question. Just click the 'submit question' one time. Although sometimes slow, your question/answer will post.
Best wishes ;-)