M.T.O. UNLIMITED'S "StraddleBag" is perfect for your wireless receiver. It hooks around your camera handle for safety and allows you to loosen the bottom strap to change the battery easily.
Lightweight but sturdy, this unit takes a beating. These are available in double and single receiver versions.
A clear window on the pocket let's you advertise your business cards and the inside webbed pockets are for heater packets for those shoots in cold weather.
The Single StraddleBag fits over the back of the battery and is secured with a piece of velcro. (MTO-SBW1).