Make sure your original stays original: The original condition of your classic BMW can only be preserved with Original BMW Parts. And this is why you will still be able to get the reproduction parts you need. Newly produced or reissued parts can be found here.
To quickly jump to a specific production line (e.g. E12) simply use the search function your browser provides (usually opened pressing Strg/command + F) and fill out the search field with the respective production line.