Martin, my guess is that either they are shared with Pantera, or they are fully unique. Wilkinson supplies these pieces for Pantera, see the picture https://pantera.infopop.cc/topic/mangusta-lock-set
But otherwise, I think at least the collar you need to replace is probably unique: I've looked and cannot identify which car used the same cylinder for a trunk lock (its not a Fiat 1100/1300, nor an Alfa share as I can tell---remotely maybe an Alfa Giulia SS) but as a trunk pushbutton, that supporting sleeve is completely different...
...or, maybe a place to start--take the trunk latch from a Pantera first and cut it down...Lee