The ceramic ones were BOSCH and a disaster and production change replaced with conventional metal BERU plugs. This was a few years before your car was made so I'm sure not ceramic. The ceramic had a white band and metal had a terracotta coloured band but some aftermarket have a black band. It is of importance because the two types are different volatge and so the ECU needs coding to avoid inoperable or blown glowplug.
I would just stick with BERU. I fitted NGK but if I would just get BERU if doing again as they were 2mm shorter.
http://beru.federalmogul.com/en-gb/e-catalogue/vehicle
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