Rock Auto as they are a major online parts supplier ... On the site you enter the year, make, model, engine size etc and it pulls up a list of your available options.
You likely have a better chance this route as there are C3 owners on the forum but some members are more active than others and most discussions are related the newer generations of C7/C8.
You also have members who owns multiple generations and are very knowledgeable but might not be online as frequent as others. Good Luck and Hope this Helps!
PS: Once you go on the site you will need to start from beginning as I don't know the exact specs of your car as there were two engine sizes and that of course determines the appropriate parts. Below are the two engine size options: