Would it be reasonable to think that with a decent enough Disguise check that a Spiritualist's Phantom could be made to look like a living being, and not a Phantom?
I figure a Hat of Disguise would do the trick, but there's always the occasional person who can see through illusions.
A phantom is an outsider, so it'd be easier to disguise them as a tiefling etc. rather than a human. Disguise self (which a hat of disguise uses) actually specifies the same type. Mundane disguises would take the different race penalty and possibly more but aren't necessarily blocked from disguising an outsider as a humanoid.