I've been asked a few times if i do work on old poker machines.. I've done a couple of old one arm bandits the last couple of years.. but i dont advertise it since i've been told that i stand to get into a lot of strife if i restore one to accept and pay out coins and the wrong people find out about it!! Now i don't know just how true this is but its something i always keep in mind anytime i'm asked to repair one 
I won't touch the electronic variety (with CRT screens etc) but i'll usually look at the old mechanical ones.
I have one here to do at the moment for an AP member 
I'm not sure what the law is exactly, but I know that the Bally Bingos were deemed illegal to operate in the mid 90's, but you can own one in the home. I think there was one one display in a shop in Fitzroy a couple years back. Just don't operate them.
I think that if you are a restorer, you should not get into trouble. Maybe a question needs to be directed to the Police so they can point you in the right direction. There is a relevant department.
