Have a used Seizmik rack for sale. It is in very good condition. I know it will fit the 2008 to 2010 Rzr 800 and because the rear box is the same, it should fit the Rzr 570. It may fit later model 800’s but not sure. I believe this is one of the best rear racks made for the Rzr. It is hinged and can be lifted to access items in the lower cargo box.
There are several stock photos here on the forum.
Asking $150 or best offer, for local pickup in southwest Idaho.