I bought new patio furniture cushions this summer. I ordered them online from Arizona Cushions. Their custom cushions allow you choose both the firmness and the thickness of the foam and the fabric, of course, so I got exactly what I wanted.

This is what the old cushions were like:

They are plastic with one side covered in cloth. I think someone gave this set of furniture to my folks back in the mid-1970s, and these cushions are getting a little worn.
The metal part is still good, and we love the new cushions.

I inherited this house and all the contents, and usually buy used furniture at auctions, so it's a rare day when I buy something new that I really want.