http://www.sounddevices.com/products/cl2/
I believe this is close to what you're looking for. It doesn't have a level meter on it but gain is controlled from the boom pole then. Then again it's best to trust ears over a meter anytime. It only controls 1 input though and is limited to sound...
Just a heads up the electricity discharged by a taser plays hell with condenser microphones. Be sure to use a dynamic for the recording. Also if you're going to nail someone with the taser you'll probably have their noise in the recording. Consider getting a pig thigh from a market and shooting...
Itu Standard are always subject to change but currenly there are meters that follow current standards. Wave loudness meter and Izotope's Insight plugins are examples. There has been a shift from peak metering to average metering which makes it a guessing game to follow to a T with out the meter...