Yep, go grab some batteries quick fast!!! In the meantime here's what I've found to be good non scale measures
Level 1/4 cup of porridge = 1oz
Level 1/4 cup of bran flakes = 1oz
2 tbsp muesli = 1oz
As for cheese I always get those 30g pick & mix ones from M&S
If you can't get a set of batteries soon then you can stick with things like Alpen light cereal bars, toast, weetabix, oatso simple, ryvita etc as your HEBs...