I have a regulator exact same as the one below, while attached to my small tank today i knocked the whole lot over and the gauge on the left that tells you how much is left in the tank got banged up bad.It's not leaking near as i can tell, however it is no longer registering at all. It would be easy enough to replace i reckon but where would i get just that gauge on its own ? ??? ;D
http://www.adverts.ie/crazy-random-stuff/co2-gas-regulator-for-homebrew-craft-beer/2214570