A tiny meal might work, is there a recipe for something you've tried? I bought two cases of quest chips and they worked well(vs buying Doritos or chips)for whenever I had a urge to snack at work.
That's funny I was actually gonna suggest the quest chips if looking for that type.
Beef jerky is another great option.
If you're looking for something more "homemade" you could bake some protein goodies (like muffins, cookies or breads) and take some with you.
One thing I also suggest is just fun flavored gum. Your mind equates chewing to satiety to some degree so just having some gum (which is usually like 5cals) can really help kill a craving when you're not really wanting a meal