Can you make up a last name/surname that does not (yet) exist.
Non-existing here means that your search in Google or any other major engine will return 0 results and/or did you mean….....
Suppose you want a last name for a novel that you (want to) write.
Or you are thinking of starting all over, on a Caribbean island, with a new identity, and a new name.
The name must not raise suspicion, therefore it must sound plausible/believable.
So, make one up, check it on Google (Bing, Yahoo, WHY, etc.), and place it here if you please!