If you are out camping you can pick up supplies in the General Store or stop in one of the souvenier or gift shops for a local craft.
Inside the the state park you will find excellent Indain crafts in the museum to purchase or to just view. It has a post office there also to mail some postcard back home
What to buy: Authentic Indian Crafts...blankets pottery, baskets.
What to pay: You can find something for every pocket book.