432 would be suitable however I highly suggest buying a plastic (grp) prop to test first before committing to an expensive “metal” prop as it’s cheaper to test the loads and performance with out the larger price tag.
Once you are happy with the props performance you can go ahead and swap, however avoid those bronze ones you would want a berillium for ultimate performance.
Check out https://www.prestwich.ndirect.co.uk/hdwraccs.htm
it’s where I get the majority of my power boat parts
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