Peter. There is a BOC in Glasgow where you could get the cylinders mentioned in the previous post by BHornsey. I have looked into using BOC in the past but ended up getting fire extinguishers. The smallest cylinder they do is about 3' high and about 6" wide so more manageable than a 5' one

Here is a link for BOC cylinder specs..
http://www.bocgases.ie/saftey/cylind...inderchart.pdf

cheers
Neil