In a message dated 12/22/2004 8:00:54 P.M. Pacific Standard Time, jbcast at charter.net writes: Francis, go to an automotive head shop, they usually have plenty of old valves. Imports use an 8mm stem, within .oo2" of 5/16". The stems are usually fairly easy to drill, grind a flat to get started. J.B., Thanks for the tip. Francis Maciel Santa Maria, CA