Can I produce my own Planning Poker cards and what is the cost?

Yes. You will need to obtain a license at: https://www.mountaingoatsoftware.com/agile/planning-poker/license

All licenses are royalty free. After completing the royalty agreement in the link above, please submit your artwork to info@mountaingoatsoftware.com for approval. We will review the artwork to determine if the term “planning poker®” is used and if the trademark symbol is properly attributed to the term in every case. In addition to using the symbol when the term “planning poker®” is used, you also need to include the following language either on your card box or on one of the cards in the deck:

PLANNING POKER ®  is a registered trademark of Mountain Goat Software, LLC
Sequence of values is (C) Mountain Goat Software, LLC