The campingaz C206 piercable gas canister is readily available here. However you need to buy an adapter from Europe to use it for the Jetboil as it uses the threaded valve.

Markill adapter from Germany


Transform a puncture-style gas cartridge into a re-sealable cartridge(EN417). Will work on most Camping Gaz® type non-resealable canisters easing your worries about obtaining re-sealable canisters in far flung places.

Karrimor Go Gas power pak adapter from UK.