Don't know how the pushbutton cable is made, bit I do know the one for Mangusta is just bulk wire with screw-on-nuts you can buy at Home Depot. Youi may be able to just get a new wire and feed it thru the original sheath. If not..
Years ago I had an issue with an obsolete gas pedal cable (429 SCJ in a Mustang). So I basically got 2 new different cables for other cars, that had 1 end the same, then cut and soldered them together to mock the original.
Now here is the tricky part, I used the original sheath, cut both cables 1½ longer than the original cable's lenght, then silver soldered each individual braid, stagered (your welds should spread over 1½ in so they are stronger and so not create a bulge.
Denis
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