The only removable back headlamp bowls I know of are for the Alfa spider. They are 7" but at £70 +VAT + P&P they are not cheap.
I presume you would also need to buy the correct headlamp units to fit them.
Purchase from any of the classic alfa suppliers such as
https://classicalfa.com/products.php...VER-SPIDER-105
or
https://www.alfaholics.com/parts/105...lights/spider/