Here is a scan of the old Greyhawk map that was in the trove of D&D material the Len left behind. It is a copy, most likely made back in very late 1970's, of the made that was made to prepare for the upcoming publication of the Greyhawk setting. Len who was a friend of Gary Gygax, but didn't work at TSR, was probably given one to be able to provide feedback, and kept it in his D&D notes.

You can download a high resolution image of it here (23MB; 6531x5009px): https://annabmeyer.com/Downloads/lakofka/Greyhawk%20Map%20Old.jpg