I had been exchanging some emails with Lee of Custom Upholstery:
They make some nice barneys and weather protectors. He's indicated that they need a camera "in shop" to design barneys and rain covers.
Since I'm East-Coast yo, I cannot help here. Anyone out west want to run over to Van Nuys for a few hours and get this project started? It's a hole in the accessory line for sure. I don't mind the clear garbage bag, but a real rain cover would be slick. And a heater barney would be nice too.