Depending on how those are secured in place, you may be able to have those custom made. I've used Cushion Source over the years and they do a great job. Very professional. Lots of fabrics. They do custom shapes where you send them a pattern to get the angles and curves right...
I've used Cushion Source over the years and they do a fantastic job. I don't think they are specific for SeaRay but they do all sorts of custom and will even let you send in patterns if you can make them. https://www.cushionsource.com/