But really, just how much of organisms constitutes molecules that can be mirrored? And whether or not a lion's stomach can actually extract nutrients from a dead mirror gazelle, the mirror gazelle is still very dead. Even if it wasn't ripped apart, stomach acid is unconcerned with what 'handed-ness' a molecule is.
Recently it was proven possible to construct an organism through synthetic processes. This is still limited to very close copies of the real things, but could be adapted to produce reverse chiral molecules.
Edit: Although, the added difficulty would be the need to reconstruct a cell completely out of mirror molecules for it to work. In the case above, the genome was injected into an existing cell and left to replicate. So it's not quite a trivial thing to do.
