Obsolete

I ordered a screen a week and a half ago from mp3car.com and just received it last week. I got it installed in my car and everything, but the screen is dark. Now I know that the backlight of the screen or the invertor is dead due to if I look at it in the right light I can see the picture of the menu still, but if I look at it head on I don't see anything but a black screen.
I sent a RMA to mp3car.com last week and then another one earlier today, but I've been reading about how no one's been getting a response from them so I called their line, but it was busy.
Now my question is this... I want my screen fixed, but I was wondering what I should do about it because I don't want to wait around forever to get a RMA.
1) Is there any way that I could fix this myself or have them send me the spare part that I need?
2) Would it just be easier to go to Xenarc and buy another backlight or invertor? I don't want to spend extra money, but I need this fixed before next Thursday.
3) Also is there any way to tell if it's just the backlight or just the invertor so that I can just buy one instead of both? Thanks for any help in advance.

MP3Car.com