you're probably right, better off on eBay. probably worth a pretty penny too.I don’t see a fresh water pump but check here for complete kit
I suspect that unless you need hot water desperately there is not much point now from a corrosion point
it might be worth selling what you have as there is likely to be a demand for them
https://www.volvopentashop.com/volspec/en-GB/Details/PentaPartsCatalog/7742230_086?path=MarineDieselEngines/7742230/7742230_90/7742230_086