There is an instructor at Curtis Aviation in Camden (at the last I heard of him he was still there) by the name of Jim Drinnan. Suggest contacting him through Curtis and ask him if Skysigns is still running or at least where you might be able to do some training. He/they might be able to point you in the right direction if they no longer operate/do the training. I trained with them 12+ years ago and did some banner work in a Maule after it.
Regards,
OpsN.