When its worn you can replace it with any "trunk weatherstrip" (not even sure it's called that way) if its long enough. Just cut it to size and make sure the 2 open ends meet up on the bumper side of the trunk (not the window side). I always go to breakers for stuff like this, just search a few cars with large trunks (longer weatherstrips) and see if the strip is in reasonable condition you should be able to get it for less then 5 pounds.
You don't need sealant or anything just 2 hands
