The handle itself (once the metal trim is removed) looks like this:
The top is part of the entire plastic piece and if broken off would be impossible to replace by itself. If it popped out at the bottom (which is must not have), they it should go back in but would need to be fixed to stay there:
We have plenty of driver's side panels but sold out of the right side, otherwise we would help if your warranty comes up empty. We wonder if your comprehensive coverage with your auto insurance might cover it, not unlike a broken windshield? Might be worth asking...