I'd like to get into the action here, as I too lost my working sunroof recently to the inevitable failure of 90's vintage crappy cast metal parts. In my case I need a Left Cable Assembly 1h0898015a. I am a novice, but getting up to speed with 3D Printing (Biqu B1), and found this really awesome effort to build a 3D Printable Corrado Parts Database, from some guys over at another forum.
3D Printable Corrado Parts Database
When it comes to scanning/CAD and printing metal parts for Corrado, I am definitely interested in how feasible/economical this would be. Found some companies out there like protolabs.com.
In any case, here's a pic of my broken 1h0898015a. It is ready for replication !