I "used" to pick up those socket set boxes all the time back when I was swapping (before C-19 and when I had a bit more time on the weekends). Those SK boxes can be spotted a mile away. I have more than my share now, and many of them have been filled (from being empty) to go on the collection shelf. I really like the old SK wrinkle finish boxes. Many of those had partial sets, and I would build them back up with the vintage pieces.
Nice find!