This just in from Gunnar:
[Enclosed: Two more caricatures of Walt. One of them is very well known and probably one of the best (above). Anyone who could make a guess at the artist that drew it ?
The other one (below) - recently sold on ebay - is described as drawn by Kopietz (drawn sitting on Walts shoulder), but I would think that Carl Barks was the man behind this drawing.
Finally here is a photo of Walt and Kimball with two caricatures of Walt on the wall. Kimball was appearantly not afraid of showing them to Walt. I would really have liked to view a better version of the drawing of Kimball and Walt in WD's office.