I saw that pillow, and I thought it would probably be pretty easy to make. Just cut circles of fabric, stitch around the edge and pull to tighten to desired amount and flatten with the gathers to the side. Sew or glue to a purchased round pillow, starting from the outer edge and working into the center. You could make the circles slightly smaller as you go towards the center. The center would be one that you would sort of fold or pleat, as in the picture.