A friend asked me to look out for either a set of front seats for his 1994 XJ40, or for at least a correct AEE Doeskin seat cover. Its a kind of beige I think.
I checked Aldridge trimming in the UK, its 870 pounds a pair, plus VAT.
Where are you and your friend located? Some vendors I’m aware of that will sell X40 seat covers include GAHH automotive and World Upholstery. I’ve used GAHH automotive for an XJS seat cover and was happy with the product. Search the forums for their names and you should see some reviews on them, as well as for Paul’s Jaguar. I’ve seen positive reviews for all 3 with regard to seat covers for older Jaguars.