Esc is before edis. Basically just another kind of ignition module Richie.

In answer to the OPs question, yeah scrappy or ebay for an esc, look for banger racing etc, the banger boys love esc.

Megajolt uses edis but no esc, edis modules are easier to find, you can get fully tested/refurbed ones of the net easy, and there's millions in breakers.

Nodiz on the other hand has it owns drivers and modules internally and will run a coil pack straight out of the box