Water Box 2005 Mainship Pilot twins

[Bulldog59]

Have lost cover to box at bottom of hull that services 5 water inputs (mains, gen, A/C and head). Anyone know who might have a mold to reproduce one or experience with a different fix? Considering stainless but concerned with growth that would occur since anti foulant doesn't work well on stainless that you can't frequently access such as inside the water box. Also anyone having pics of the box cover to help determine how and where the slots are for water passage into the box? Any help appreciated. Thanks