I bought that exact game from a guy who bought it at a Woodward & Lothrop store in 1980 or so... As the story goes, Woodies had bought a bunch of old pinballs from a local distributor and sold them through one local store in the Columbia MD area (maybe the mall... not sure). I bought it for 100$. What had happened, is that over time, the ball inside the game rusted, and as it was played, spewed all that rusted steel all over the playfield, and by doing so, protected from further abuse... I went through that game with a fine tooth comb, and afterwards it played like a champ. I picked up an NOS plastics set from CA; other than that I believe the only other parts that required replacing were the flipper coil stops and flipper bats. I tired of it after a few years, and sold it at the York show. That buyer kept it a few years and eventually sold it to the museum... I owe that museum a visit as I've heard it's an awesome venue.
Don O