Nah, the smoke monster can only take the form of people who are dead. Jack's dad's body showed up at the island, Locke's body showed up at the island, Echo's brother's body was on the island after he died in the plane crash, Ben's daughter didn't show up until after that crazy dude killed her. I think the Smoke Monster came as Richard's wife, but that doesn't make sense cuz her body was in Tenerife and not the island.
I'm still wondering why the Smoke Monster is permanently in Locke's body though, or how he lost his original body. All I know is that Jacob told them that in order to come back to the island, they needed things to appear as close as possible to the original plane crash, which included the people who left and a dead body. I think it's weird that Jacob would tell them to bring back a body, if the Smoke Monster could take that body over. This shit is driving me crazy!!!
But I don't think Jack's dad has appeared off the island since he died. All the flashback scenes were Jack's dad prior to his death, and in the flash sideways scenes, his dad is dead prior to the Oceanic flight back to LA.