Don’t know about Mr. Fiat, but I just bought a replacement taillight sets from Vintage Euro parts (Lens and chrome bezel). The first set, ($600) was a low quality set. Bubbles in the chrome……
After I talked to them, I was told that this set is made in Taiwan and is in fact a lower quality. They are also selling a higher quality set ($799) which they buy out of Germany. I am in the process of exchange and if interested, I can let you know what I think of the new one, once I get it. Working with them was very pleasant and in their defense they actually state on their side that it is a B-grade, which I missed.
They sell lenses only as well and you might want to give them a call.
Dirk