I primarily use muscle milk. 5lb costs me around 45-50$. I get the big tub of Vanilla (32gm per 2 scoops) and Chocolate whey (25gm per scoop). Mon - Fri my breakfast consists of 2 scoops vanilla, 1 scoop force factor greens, 1 scoop force factor beets, 6oz berry flavored kefir, and 6oz V8 Ginger lemon beet juice all shaken up. Sometimes I’ll also add 1/2 cup of Oikos Pro. 50-60gm protein. Very nutrient dense and definitely not low calorie.
My mid morning snack is 1 scoop chocolate whey, 12oz unsweetened almond milk, and 1/2 cup Oikos Pro. Again, about 50gm protein.
Anyway, I digress. I certainly haven’t searched too far and wide but 5lbs seems to cost about 50$ regardless of brand or source. There are certainly more expensive brands but haven’t found too many cheaper options that don’t also taste cheap.