Amazon has EXPO Dry Erase Markers 8ct for $5.97 (Reg $13.49) with free shipping on orders over $25 or with Amazon Prime orders.
Use Expo dry erase markers to track, schedule and present your point in a brilliant fashion. Intense, bold colors take center stage even from a distance. You can get Expo wet or dry erase markers in a wide range of tip sizes, ensuring your point gets across. Erasing is also a breeze, wiping away cleanly with a cloth or Expo eraser from most non-porous surfaces.