“This, milord, is my family's axe. We have owned it for almost nine hundred years, see. Of course, sometimes it needed a new blade. And sometimes it has required a new handle, new designs on the metalwork, a little refreshing of the ornamentation . . . but is this not the nine hundred-year-old axe of my family? And because it has changed gently over time, it is still a pretty good axe, y'know. Pretty good.” - T. Prat…
If any subset of the new ship is a subset of the original ship then surely. But this also raises the question if we take a subset and build a new ship. Which is the original?
Another interesting take is to introduce non-physical attributes such as a name of the ship. That way every piece of wood could be changed but the name attribute would still make it a subset