Fagor 8040 control comes to mind as a machine control that is easy to program using the built in conversational software.
$15000 here. I think the pound is worth abouy 2 of my $.
I may be wrong but IMO anything that you are going to coble up out of free controls and software will be a terrible training tool.
There will be idiosyncreses, and glitches to work around all the time and it will not be straightforward to use, this will frusturate and alienate the students and is not representative of todays working CNCs.
If you are not teaching the CNC itself then my above point is moot, Do as you will.
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