Hi Paul
Welcome to the Forum
Sounds like you have a Project on your hands, at that time I believe BMW used both Bosch and Magneti Marelli
Check www.realoem.com put the last 7 digits of your Vin into the search box (your model should be in the Classic section. Then check the Fuel Supply foe your pump and allied stuff once you have the part number google it to find the best price and delivery
Hope this helps
Dave
P.S If you double click the part number it should show a list of other models and alternates.