I found the LEGO Two-Face hairpiece at the flea market a couple weeks ago. t would be pretty useless if I didn't own the Jekyl/Hyde minifigure. But I do, so I replaced the top hat with the hair and voila!
Even though the look lacks the general two-color theme of Two-Face, the clean side/torn up side create an effective Two-Face. Maybe a seventies era Two-Face with those side-burns, but a Two-Face nonetheless.
BONUS: Two-Face enjoying a tea party with his princess friends. Even with only half a handsome face, that Harvey Dent is still quite the lady-killer!