This ISM band runs from 13.553 to 13.567 MHz - a 14 kHz wide bandwidth. It won’t support more than one or two AM transmitters.
This doesn’t seem like a good idea.
* If you want to stay legal, your output power will only be a few milliwatts at best.
* You are going to be competing will all sorts of industrial noise emittters.
* You are going to be interfering with a number of established hobbiest beacons.