Hancock's of Paducah. $19.98.
http://www.hancocks-paducah.com/Item--i-KC-CARD
They also have excellent standard prices on Kona Solids with quantity discounts. If you buy a half yard, it's $5.98/yd; if you buy a full yard, it's $5.38/yd; and if you buy a yard and a half or more, it's $4.78/yd...plus they carry all the colors.