No but making your own patterns should not be hard to do with cardboard and simple if they are rectangular by using a tape measure. I have made many for my boat. And seating material can be easily made using foam cushion material from a local distributor. Beware-- it is expensive.
Note the foam comes in different durometer ( hardness). If you purchase
new material and maybe you should to make your cushions
better than originals, you should not use the same material for the backs as for the seats. The backs should have a softer material.
I found the easiest way for me to cut the stuff was to place a 2x4 or other planking on top of the material being cut. This allowed me to use the edge of the plank as a guide both for the vertical cut and the length wise cut. OH-- an electric
knife is what I used, it works well. I tried cutting some on my cabinet maker's saw and it just made a mess of things.