I do believe YOU can replace the LED or bulb, not sure exactly which light you are talking about. I have never had this control unit apart, so I believe the amber indicator in the knob is an LED, but the backlighting for the unit is comprised of small bulbs that can be found (usually) at a local radio shack.
If you are going to replace the entire control head, then you have nothing to lose by disassembling your existing one and trying to replace the bulb or the LED. It would require a small soldering iron and some steady hands.
I had a 2003 Vette where I replaced all the backlight bulbs with blue LEDs in the radio, AC control head, all the DIC switches and the door control, windows switches. The radio and control head came apart very easily and it was not that bad of a job, other than to get the LEDs to light evenly in place of actual incandescent bulbs (LEDs tend to be more directional).