Maybe this will help, I am making meatloaf for dinner, so I put it in a skillet first.
About 1600 grams or about 3.5 pounds of ground beef and pork. Tfal skillet 10.25" diameter, meat is about 1.25" thick.
I would think add another 2 pound to it, in a 14" skillet to shape and after cooking use 12" pizzas. Estimating the 3.5 pound I used in the picture, in a 14" would be 0.75" thick depending on how packed it was.