Which seats are you looking for? They can be hard to find as exact replacement. For example, if you are looking for a back to back lounger which came standard on most cuddys, the typical ones you will find only have a 10" high base, whereas the base on the original seats is about 16". That extra 6" makes a big difference. Try
www.veada.com. They make some pretty nice seats, and you can get them in whatever base height you want, plus custom colors. They have a nice lounger with a 14" base (you can go up to 18") with storage underneath for $307, including shipping.