I'm going to re-ask for help on this one as I got no response to my first asking for help. I picked up a Heath HG-10-B vfo that the NE-2 bulb in grid block circuit that is broken. Since it can't fire (-90 volts across it) the vfo oscillator continues to run with key up.Where can I find a replacement neon bulb?? Thanks for your help in advance. Sam K5SW