As previously mentioned these Brembo discs for an Opel Omega B is the closest match I have been able to find (using them on my 73 Pantera). What needs to be modified is: 1) 5 new Stud holes drilled with the correct pattern/diameter 114,3mm and 2) the center bore needs to be enlarged to fit the Hub (I don´t remember the exact number)
You have to carefully grind a few tenths of a millimeter of your calipers in a few places as this Discs is 286,0mm diameter. I have fitted Volvo 4 pot Calipers but they work also with the stock Girling 4 pot.