For people with hunting dogs: What is the best cold water/weather hunting vest for a dog?

I have a 1 year old chesapeake bay retriever that is in training for hunt trials as well as to hunt water fowl. He usually doesn't get cold but when breaking through ice in the water and when waiting for the next retrieve, he sometimes shivers. I want something to protect him from the cold as well as to protect his belly from getting scratched. Does anyone have any suggestions as to the best vest for my needs? Thank you