It's CCK068:
HEL Performance Braided FULL LENGTH Clutch Line Volkswagen Corrado (1989-1995) | eBay
HEL Braided Clutch Line Hose VW Corrado Master Cylinder Slave 89-95 CCK068 Y3305 for sale online | eBay
Volkswagen Corrado All Engines (1989-1995) Flexible Braided Master Cylinder to Slave Cylinder Clutch Line | Corrado | Volkswagen | Clutch Lines | Braided Lines | Car (helperformance.com)
Oddly, didn't find it on their website when I first looked, but must just have missed it. Only difference from the standard fit is that I don't think it will clip into the first clip after the master cylinder as that will put too much of a bend in the line. Should be able to get the grommet off the original and slide it on so that it clips into the bracket welded to the side of the chassis near the battery tray.
I'll take a photo when it's on the car to illustrate.