On 27 Mar 2007 01:38:58 -0700, wrote:

If not, where could I get a small bottle (1L) which is capable of
holding a measly 8bar which has a suitable thread?

you could use a fire extinguiser bottle. sometimes available from
scrap merchants i gather.
That will probably have a sensible sized thread on it already. The one
hanging on the wall in my office at work looks very similar to the
fittings on my pub gas co2 bottle (which are avaialble from welding
suppliers).