Based on the way you worded your issue, it would appear that you are not familiar with retrofitting in general. There are many, many potential controls that you can fit to that machine, but, a majority of them will need a quick study of what it all means to swap out the control on such machine.
That said, if you believe that you will need a control supplier that you can ask to assemble all of the correct components necessary, and hold your hand thru the project until it is up and running, you might want to work with Flashcut CNC. It is likely that they have already supplied replacement controls for that very machine.
If on the other hand, you can afford the downtime and want to learn all there is to learn about CNC controls at this level, all you have to do is search the web for CNC Controller, and the majority of the links that will pop up are going to be controls targeted for your exact type of need. And, most of them will require you to do your own legwork in understanding what you will connect to what, and what you will need to configure to what in the software.
Choose wisely. You will find controls for as little as Free in LinuxCNC, practically free as in the configuration of a $4 Arduino and GRBL, to many thousands of dollars. Only a lengthy time reading through the forums of each (when they have them) can give you some insight as to whether you should try one or not.
The last bit of advise is simply to not give up. If the hardware is good, the machine can be made to run again, and likely run much, much better than it ever had before just because controls have advanced so much in motion, features and user ergonomics. The equation to a good running machine is simple. You keep throwing money at the project until it actually does work the way you need it to.
Here is a link to Flashcut's Retro page and I see Techno even listed there for your peace of mind: https://www.flashcutcnc.com/retrofit...rline-tabletop