NY, try cable connectors, refine with electronics, possibly water proof cable connectors. It may take a bit of creativity but even connector manufactures might do. We have a electronic plant here and I go thru them. I have in the past searched and with some different tries have gotten "hits". Once you get in the ball park the search suggestion are a great help also... the world if full of "connectors" and especially in the low voltsge/amp electronic use. And they recognize the need for waterproof also..
chuck