Ok - here's what i want to do. I want to use a Novatac clip on my Surefire Fury so I have the option to pocket clip it. The clip fits the flashlight body ok, but there is too much gap between the body and the tailcap when its screwed down. Where can I get O-rings that are the right size to fill this gap and tighten up the pocket clip so it doesn't spin and wobble?