i made my own for the same boat on a home sewing
machine. for about $100, i made brand new covers with new zippers. I use the old foam and just shook baby powder on them to make them smell newer. The old foam wan not compressed or shot...just a little boat smelly. It was somewaht time consuming, but rewarding when done. I did the single cushion in the rear, both starboard and port and two bow cushions. Went to JoAnne fabrics on a sale day...cheap.