In top of double boiler, place clam broth, 1 tablespoon of the butter, 1/4 teaspoon paprika, celery salt, and Worcestershire sauce then stir gently. Add oysters and simmer just until their edges start to curl, about 1 minute. Stir in chili sauce and half and half and heat through. Place a slice of toast in warm bowl, pour oyster pan roast over toast, and float remaining tablespoon of butter on top. Sprinkle with a pinch of paprika. Serve immediately.