They did claim "up to" 50,000 shots per 16oz canister.No. He means propane, the Tippman C3 gets around 16000 shots from a 16oz propane canister if I remember, Its a pump, and gets a bit warm, but as I understand they are disposable canisters, and it may be tricky to find the right kind in the UK. Give Jimmy at Warped a call, I seem to remember seeing a C3 in his shop, he might be able to help
Should've googled that one first........Propane !!!!!
I think you mean a C02 tank, I'd recommend looking for a 20oz if youo're going down that route as they are the most commonly used. You might find one for sle on the forums or most of the paintball stores in the Uk would sell you one.
Look at the suppliers section on these forums for details about stores.