A very, very small handful of books were restored by Calvin Slobodian decades ago, and another very, very small handful may have been purchased second-hand, rather than directly off the newstand.
From Doug Schmell (www.pedigreecomics.com):
However, and perhaps most unfortunately, two known Silver Age collections that appear to have the characteristics of these more well known pedigrees have not been afforded this loftier status by the experts at CGC. Both the Slobodian collection (from the private collection of Calvin Slobodian from Calgary, Canada) and the lesser known Edenwald collection (from dealer/collector Conrad Eschenberg of Cold Spring, New York) are both high grade collections, purchased by a single owner, in which the books share a common look, feel and smell.
What separates these two collections from the more nationally recognized and CGC certified ones mentioned above is the lack of sales records and data needed to track the dissemination of the individual issues once brought to the public and sold. Another factor, solely in the case of Mr. Slobodian, was the existence of some restored comics among those he had purportedly purchased off of the newsstand, causing a lack of certainty as to which books were actually bought by this original owner.