This thread is so old that bstuart has probably made meatballs and spaghetti again by now.
Nevertheless, one need not make a huge pot of S & M. Aldis sells frozen meatballs in a container, fifty or more meatballs.; Take out as many as you like and cook a few stalks of spaghetti and you are home free. I can make sauce in a big pot or small.
My preference is Hunt's original, souped up with onions and bell pepper, some peppercorns and garlic. If I do not have meatballs I just fry up a bit of hamburger and mix it in the sauce and put the whole thing over spaghetti. Wife likes to put cheese over it at the table. Me, not so much.
Made that way I can freeze whatever I do not eat and use it one portion at a time.