Came across this at:

Search results for: 'Jaguar' - Mac's Radiator Online Store

For 1981-1987 XJ6

 

Not cheap, but in my 20 years of owning my '87 I replaced the plastic one twice then finally gave up and found an Australian seller on eBay making metal versions. I have no recollection now whether it's Al, Steel, Brass or whatever (it's painted black) but I do know that it outlasted those plastic things by several years.

 

looks good. Expensive but it is an improvement. However, the shape of the tank is diffferent than the original.