I do ham and cheese full fibre toasties. About 150-200kcal but very filling. Not having any 'bad' snacks immediately available in the house also helps a lot.
I guess with everything combined, one toastie is closer to 300 kcal, (local nutrition org says 81kcal per slice of bread) and doesn't really fit the low cal request, it's true.
It works so well for me for staying away from just rawdogging a whole bag of potato chips, which isn't even that much more calories, but the type of calories are way worse.