Source for left hand 1/4" pipe plug?

["Aric Datesman" <adatesman@speakeasy.net>]

Greetings all,

I'm at wits end here and need a bit of help locating a part for a project.
Anyone know where to get a left hand thread 1/4" NPT plug?  Can't find it at
McMaster, Fastenall or any of the local welding or plumbing shops.

I know they're out there because I have one (unused high pressure side of a
CO2 regulator) but damned if I can find one.

Thanks much!

-aric.