Is it a Whale pump?
I think it's a Whale pump, Chris. Will probably go to my boat Wed. 10/18; if so, I'll look at what I've got. I have the manual holding tank pump, as well, and it appears to be the same model. You can contact Whale at whalepumps.com. I would think they would be able to help with a kit. Mine is an '87 model, so a pump rebuild kit(s) is probably an overdue maintainance item for me, too.