I have actually come across those on eBay before. Keep checking there would be my suggestion. I bought a replacement from eBay for only $20 plus shipping. The one I bought was a bit worn and faded, but I just needed it for a tinting experiment.
I have seen auctions with both tail lights and the center piece got for $50 total.
I have seen auctions with both tail lights and the center piece got for $50 total.