Looks like you have a Lockheed master cylinder on your car. If you give it a good wire brush, you might find the Lockheed part number on the r/h side, like 993.
Being not familiar with Aurelias, I believe the brake system was made by SABIF. M/C can be bought from Cavalitto and Amadei Ricambi and others. I am sure, Aurelia owners in this forum will know more.
Karl