Outer Limits 4x4 Board

I have a 2001 Defender Extreme and I’m get sick of the rear sliding windows rattling all the time and leaking when it rains. I know it’s a defender so it should let in some water but I still want to fix it. They are also a pain to access the rear of the truck through.

Has any done or heard of a mod that replaces the rear windows with something else that would solve the problem?

Thanks for any help.