Dropped phone and screen's back LED light isn't working.

I've dropped my Galaxy Note 4 on a concrete floor and te LED backlighted screen isn't lightning up. My questions are:

1. Is there a way to have the LED backlight replaced on its own, or is the entire assembly for the front screen in need of replacement?
2. In the above question I need a complete cost assessment to determine worth of replacement or need of another phone. I'd like to keep this one because it's been useful ever since I've had it in 2015. I'm a storm hunter and the device is part of my hunting and other important aspects related directly to meteorology.

I know the phone works otherwise, there's a few peaces of software in it that I use for tracking of the device and I can tell it's working as in receiving calls, but since I can't see the screen without the LED backlight using it is hard because of having to unlock the screen first by password.

I've been having serious issues in the past 3 months with the insurance company that I went through at StraightTalk and it's not looking like they'll do anything about it. They've recommended buying another phone.

I'm looking for a way to keep this one and get the best out of it. And I'd appreciate any help you can provide.

Brian R Cross.

Tahlequah, Oklahoma USA.