You need to take a trip down Foulks Boat Yard on the Hamble, just before the A27 bridge. Scrap yard just for boats. They have a 40 foot container full of propellors Take a torch, copy of the Yam and Merc part numbers for the sizes you are interested. Plan to spend the morning there, its a facinating place but don't take the wife/gf or kids. You could probably arrive by boat if its high tide.
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