The easiest solution might be to replace the aftermarket wheel with OEM. If it's from an Touring model it would likely come with the button controls. That way if the previous owner didn't cut the wires, it would be a simple plug and play.
Be aware that in addition to the steering wheel buttons, the on/off switch on the dash, and the actuator under the hood, there is also a cruise module located behind the driver's side kick panel.
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Jim
VR R1 FD
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