I found a used headliner on eBay for $80 and it happened to be about 100 miles away in Jersey. It’s been awhile since I did this but it wasn’t that difficult to remove my old headliner.
Remove the A, B, & C pillar moldings, screws under all the handles, unplug the wiring harness, and it should come out. We put down all the seats including reclining the front seats all the way back to be able to wiggle it out at an angle. Same as getting it back in with just getting angle in the right spot. It will be much easier with 2 people. Hope this helps!

Also, my LR3 does not have rear climate control so you may also have to take that into account in terms of what else is above the headliner that I am not aware of.

I guess it’s suitable, yes. But the sunroof framing and all kinds of stuff will be exposed and will look terrible in my opinion.