If the bow has a Kodiak Special silk screen, it is a bit surprising that the serial number is not "EXP." , as that is what the frame of the bow appears to be. Many other experimental Bears of the same era are marked EXP.
Probably most correctly categorized as an Experimental 1961 Kodiak Special as the Riser is most similar to the 1961 KS, and logically made prior to 1961 as the serial number with two letters followed by a number follows the 1959 and early 1960 serial numbering sequence. Hard to tell exact glass color from the photograph, but it appears to be similar to the standard 1961 KS glass color (in this case, glass color is the least significant of the three identifying characteristics mentioned).
Unusual bow, looks like it could be from the same Bear bowyer's cache that was located in the Northwest and brought to light a few years ago.