Any ideas where one might source these without a quantity limit for a decent price? Seems like they’re limited to 10 or 5 max. I’m looking to get 14 of them.
Easiest place I know of to find distributers for electronic components is octoparts:
https://octopart.com/search?q=B-G431B-ESC1
Cheapest one without an order limit seems to be Farnell!
What’s the plan? 
I’ve got a rethink robotics chassis that unfortunately is lacking in all the controls. Plan to use the B-G431-ESC in a simpleFOC over canbus with it and control it via ROS. I have a electric wheelchair chassis for it. And I’d like to get it setup with a stereo camera setup. Basically cobbling together a bunch of different things to hopefully end up with something neat.