Well, the motors are really low power types so they do not draw many amps. I am using an XTM car speedo I had lying around. It is rated for a 15 turn car motor. I also installed a cooling fan and extra heat sinks.

I think the Mtronics line, available from Hobby People, would be a good and inexpensive choice for a reversing esc. Mtronics are waterproof and can be water cooled. But I think any mid range car type esc would do the job.