I am not sure where you live but, any reputable upholstery shop can make you replacements if you don't care much about the logo. I had mine done along with the backrests, combing pads and both box covers done with white and green for $800.
I have a seafarer and had all the cushions (Except inside cabin) and bolster done for 750. Look great and they used flow through foam and mesh backings so they wont get waterlogged. I too used a local guy, McSorely Custom yacht canvas in Huntington NY. So pleased with results