After being underwhelmed with the performance of "EG STARTS 5x New 60mm Dome Shaped LED Illuminated Push Buttons For Arcade Coin Machine Operated Games" backlights I tore them apart and printed new inserts with the labels I needed for a custom photobooth.

The buttons have a nice action but you couldn't see the LED through them even with 12v supplied.

With these thinner inserts, printed in natural PLA, they light up nicely when supplied with only 3.3v from a Raspberry Pi GPIO.

Link to Buttons on Amazon: https://www.amazon.com/gp/product/B01M7PNCO9/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

Link to Photobooth Instructable: http://www.instructables.com/id/Raspberry-Pi-photo-booth-controller/