I want to buy a used cover for a 2007 Radian 65. When I look online, I only see covers for newer models. My cover is just getting a bit ratty and stained and I intend to keep using the seat for another couple of years (Thanks to this board. I assumed the seat expired in 6 years but after reading some old threads, I found that Radian's expire in 8 years. I looked in my instruction manual and confirmed it now I won't have to buy my daughter a new seat next winter. Yippee!)
The Radian65, Radian80, Radian65SL, and Radian80SL covers are all interchangeable.