If you do a google search for spaniel bowls you'll see the shape that mlynnf50 has mentioned. I have ceramic Mason Cash spaniel bowls for my two and a stainless steel one too. I think ceramic or stainless steel are the best materials because they wash well, so they're hygienic, and they're robust. But they'll be far bigger than Burt needs when he's very young so I'd suggest a small stainless steel or ceramic bowl to start with.
Be careful what you put in a Kong while Burt is young in case he ends up with an upset tummy. I use things like treats, chopped cocktail sausages, peanut butter, mashed banana, cottage cheese and cream cheese for my adult dogs (not all at the same time
) but you need to be a lot more careful when they're puppies. I can't remember what I used then, but I'm sure somebody who has a puppy now will see this and reply.