When we were taking out the plastic liners from the wheel wells we noticed that both were cracked. The passenger side was in much better shape than the driver's side. I decided to see if I could find replacements. There are no new replacement liners being made, but I did find a used set that was in good condition and cheap.
They arrived today and, although the box was just a little bit bigger than what you would need to ship a basketball, they were both in there. The picture below illustrates how they managed this feat.
Here is the passenger side liner.
Here is the driver's side liner.
They are as described with one small crack on the drivers side that I intend to patch and reinforce with POR-Patch and a small section from the original liner. You can see the crack in the picture below.