Power button fell off

As described my Power Button fell off my phone i usually kept it in the rubber cover it came with but i noticed it was getting very hot while i was driving so i took it off and held it near one of the A/C vents to cool it down. Once i got to the location i forgot to put it back in the sleeve and had it out in the open for about an hour and a half. After Leaving i used its GPS functionality to get me to the airport to pick up my parents. It wasn't until midway into the trip that i realized that the power button was missing. I works perfectly now only that now i cannot wake up the phone whenever its asleep without the power button.

does anyone know what i can do in order to get a new button? XD