Get a Escalera like everyone is saying. They are definitely spendy, but look at what we spend on games/pinballs. I just picked up mine last year(got one used with forklift option) and I am glad I did. I have moved multiple pinballs, arcades games and even cabinets up my basement stairs with ease. Should have bought it earlier and I am glad I got one.
Also, Larry is your best bet to get one or even to get parts for a used one(if you find it).