high-mount brake light, 3rd brake light assembly

I have looked EVERYWHERE for a high-mount brake light cover for my dad's 1999 Taurus Wagon. He doesn't need the lamp. It lights up. But part of the clear cover cracked off in a car wash. And after literally hours of searching on the internet, I have found absolutely nothing. The only thing I that turns up is the bulb. But he doesn't need that.

I would be incredibly thankful to anyone who can give me any leads on this one.

Thanks!

Something like this may be a dealer purchase or bought at a salvage yard.