My driver's map light doesn't work. I suspect a corroded or damaged switch contact. Passenger side works fine, have a known good bulb in the driver's side.

Can I replace the lamp switch in the dome light assembly? Or do I have to buy a whole dome light assembly and swap that out?

If I can replace the switch, does anyone know what a part number for it would be or where I could buy one?

 

Probably just a dirty contact. Take it out and inspect then clean with electrical contact cleaner.