evil_lurker - 9-1-2006 at 20:49
This may be the strangest and easiest source for metallic sodium of all.
High performance automotive exhaust valves are sometimes filled with sodium.
All that would be required is to cut, or preferably break them since the metal is hardned out the wazoo, and drain the sodium out .
Which valves are filled with sodium and how much are contained in each are pretty much unknown, but next time I go to an engine rebuilding shop I
might do some asking around.
a123x - 9-1-2006 at 22:23
My uncle works in a high performance automotive shop and had several such valves. He gave me a few one time. The steel is thin enough to cut open
using a hacksaw without much effort. It's a little annoying to scrape out the soft sodium metal because it sticks to the sides pretty well. I found
that melting it out and into some molten wax worked pretty well. I got about 2g per valve.
neutrino - 12-1-2006 at 14:44
This may be of some interest.
Magpie - 12-1-2006 at 15:03
That's a very nice website, neutrino. 
Dr.Muto - 3-3-2006 at 13:11
thanks neutrino