we went to the salvation army first, and i had a heck of a find! on the shelf, was a vintage white-box big loader, exactly the same as the one i had as a kid. i grabbed it, had a quick thought that it would be expensive, and then that i really didnt care anyway! LOL. i was surprised to see the sticker saying $4.50, and that it was push along only.
there were another two stickers on the box flap, from the DIC department store. chances are, this set and mine both sat on the shelf together.
i was able to get the chassis working without trouble... a decent battery, a couple of sharp taps and a bit of forced rolling, and she was away. the set is 100% complete, including instructions and all 12 balls. likely the best buy i have had in a while.