If you can't find one you can do what I've done in the past.
Get yourself as thin of a micro USB cord as possible and plug it into the demons onboard port. Extend it somewhere you can easily access it and your good to go.
I also hooked up the sync button NAND switch wire when I had to do this. I also had to trim the housing off the cord right at the plug in to allow room for it to fit when in the cage.
Just a suggestion as a last resort.