Solarpunk living includes a pretty strong waste reduction component as part of being environmentally conscientious. One of the simpler ways to reduce the amount of waste you generate is to cook your own food. While the greenest measuring cups are the ones you already have, if you are in need of a set, the KitchenMade Stainless Steel 6 Piece Stackable Set is the best I’ve come across. The measuring cups are each made from just one piece of stainless steel, so they are easy to clean and could be recycled if needed. Short of being hit by a truck, I don’t see how they would break and need recycling though.
Besides their indestructibility, the best feature is the little indents on the sides for smaller measurements. For instance, the 1 cup also has gradations for 1/2 and 3/4 cups. This is great when you’ve been cooking a lot (Thanksgiving, anyone?) and your 1/2 cup is already dirty. The little gradations aren’t deep enough to trap anything from getting cleaned, and I usually just throw mine in the dishwasher. The only real downside to these measuring cups is that the labels for the gradations are written from the outside. Since the labels are stamped into the metal, you can see them from the inside, but you’ll need to read backward to know what the measurement is.