Quoted from pinballlooking:
Just be aware this is an LCD screen, not an OLED screen that is in Jeremy's V2 and our V2.1 and V3.1. The LCD screen you have was only used in Jeremy's V1.0 and requires backlighting. The new OLED screens do not require backlighting. The correct screen replacement part is Mouser part number is $53.23 (971-UOLED-128-G2) unless you have Jeremy's V1.0 then the LCD part number is the correct one.
The LCD version has a built-in backlight, although it is true that the LCD isn't as bright as the OLED version, it does work fine (in fact the colors are more accurate because that's what the code was tested on.)
If anybody ever did need to replace their screen both versions are also available at Sparkfun, and the code is on my site.