The great thing about SOS is once you learn to make the cream sauce you have many options of ingredients to switch it up. Just check the salt and seasoning levels.
Try diced up hard boiled eggs, either by themselves or with meat. Chopped up crispy bacon would be good.
My mom used canned tuna and served with canned green beans.
Use chicken and add a few vegs and it could be like pot pie or chicken ala king depending on which vegs are used.
Use leftover ham and frozen peas. Good over toast or pasta. ( I hate peas but can tolerate a small amount of frozen.)
Use hard salami. I actually use this instead of the jarred beef for cheese balls and dips. I cut into small pieces then put in my small food chopper. I make a version with dill pickles instead of messing with wrapping pickles in ham and cream cheese.
The best time to buy the jar beef is around November when they usually have a display, coupons and recipe cards.
Mmmmmmm...Bacon.