I purchase juice from Regina out of California. There is a local distributor I get it from after Labor Day. If you contact them they will let you know local dealers. Just search Regina juice.
I don't think you'll find a true Cab Franc kit with the exception of an icewine style kit. That's a different beast entirely, though, and probably not what you're referring to. You'd have better luck finding a place to buy grapes/juice from.