These are the cable's numbers mentioned below however I suspect you will struggle if you haven't got the specific plugs and trying to make your own
Speaker cables
REEX0858-L (green), REEX0859-L (white), REEX0867A-L (red), REEX0860E-L (blue) and REEX0868E-L (grey)
If you have the plugs I would say any bell cable should be suffice although you'll need a tool to crimp them in place
My suggestion would be to look for another secondhand (spares or repairs) which has them and use those cables as individually they will cost you more than the units is worth
If you haven't got the manual, please find it
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