Automation help request - Audio/Video sync

Hi all - I am volunteering as a photo/video/AV person this week at a camp for children with cancer and would really appreciate a quick piece of advice.

I'm shooting video with a Canon 70D but the audio pickup isn't great. I added a Shure LensHopper mic (VP83F) which has an audio cable to the camera mic input *and* saves WAV files to a microSD card. The quality of the audio on the card is better than the mic input on the camera. So if we want the best output quality, we need to marry up the two files. I've made sure to sync the date and time on both devices as best I can.

What I'm hoping to find is a tutorial or bit of scripting advice to automate this process as much as possible – discover video and audio clips based on capture time/duration, marry them up in FCPX, and make them easy to review (maybe even export them?) There is also the challenge of limited disk space - all of the videos live on a PC or a hard drive that the Mac can only read, not write to, so I'll have to round-trip them between machines in batches using file sharing.

Your thoughts and suggestions are appreciated!