b.m.ghersiСергей demonstrates in this video, a gas canister fitting into the 650ml version. Additionally, a standard 32oz Nalgene bottle will also fit snugly in this model.
That said, gas canisters are pretty robust, you could get whichever model suits your budget / size criteria and just store the gas canister with the plastic cap by itself without fear of damage.
rarelybothThat's what I do... keep the canister separate. Let's me shove a bunch of other stuff inside my cook-kit. Works great, and has NEVER been an issue.