Re: SUREFIRE R6
Your post got me to looking for springs for a couple of Laser Products Fountain Valley, CA tailcaps. Found a spring that almost fits, but a bear to install. Best bet is to phone Sure Fire and ask for one of the older Fountain Valley tailcap springs. All tailcaps, including R6's were the same at the time. If customer service does not come forth, ask for a tech, who may be able to scrounge one up for you. They have the stuff, but probably put away somewhere. The other thing, dig around in your stuff at home and you may find one that fits, even if not a SF product.
Bill