I vote for the mini-computer:
I know you keep mentioning that you want a “laptop for FireControl.” But as BigDaddy points out, FireControl does not take much of a computer to process the gcode to control the table.
Thus: A really inexpensive way is to rig up a mini-computer (as BigDaddy mentions). I recently did this very thing and you would be amazed at how cheap it is. I spent less than $400 (already had a monitor and keyboard).