While Bear produced a large number of Kodiaks in 1959, it was a year of some "firsts" for the Kodiak; such as the coin placed in the riser and using Brazilian Rosewood for the main riser wood. From a rarity perspective, it is the wood used between the rosewood slabs that shows in the sight window: The rarest is bubinga, followed by dark brazilian rosewood, followed by maple. My guess is that most of these woods were used in the earlier part of 1959. The vast majority of 1959 Kodiaks used purpleheart for the sight window.
Regardless, maple sight window 1959s are not commonplace. Yours appears to be in very nice original condition. If it is in original condition, that is really where its value lies. They still show up every now and then (here is one I found recently:
http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=14;t=004489) but rarely are they found in nice condition.
Congrats on your find. It appears to be in great shape from your photos.....and a nice quiver to boot!
Now for the disclaimer.........Go over the bow with a fine tooth comb and check the tips carefully prior to stringing it up and shooting a few arrows! You certainly don't want such a nice bow exploding because the tips were loose or any other issue.