Lewis accepts that both these objects exist: his mereological universalism (belief in arbitrary sums) guarantees the existence of the transworld object, given the existence of the various worldbound objects.

Ar.[…]The Marriners all vnder hatches ſtowed, / Who, with a Charme ioynd to their ſuffred labour / I haue left aſleep :[…]

If a man should wish to be in some other place, it is entirely possible for him to imagine himself in that place and, diving back through the negative dimension, to emerge out of it in that place with instantaneous rapidity. To imagine oneself———

Court, city, church are all shops of smallwares; All having blown to sparks their noble fire, And drawn their sound gold ingot into wire; All trying by a love of littleness To make abridgments, and to draw to less Even that nothing which at first we were;