Looking for my 2010 E350 one button/cap that I has lost of the multifunction seat switch that is in my door. The switch has three buttons/caps. The button that I need is the one that move the head rest (small one) at the top of the switch. Maybe someone that had replace that switch can sell to me. I don't want to buy the whole switch that is so expensive, for one button/cap. Appreciate your help.