I have seven RC Marine sea cocks with Delrin thru hulls for 1 1/2" ID hose. The are made of glass fiber impregnated resin and will not corrode. The also have tails for attaching the hose. These things are strong and tough.
From an unfinished boat build. Asking $30 each, complete.
I also have two for 1" ID hose $20 each complete and one for a 5/8" at $15 complete. see pics.