The '58 Alaskan riser profile is very similar to many of the early Bears. Just a plain maple riser with a similar feel to the '55-'57 Kodiaks. I sould say the other Bears of the same years, but those didn't have the deflexed riser. The KS always had a much bulkier riser.
top is the '59 Alaskan, bottom is the '58
Here is a bunch of other '58 Bears (OK the Polar may be a '57)
I liked the way the '58 Alaskan shot. Mine was a 56# closet queen that I let go of (62# at my draw was a bit much). My '59 Alaskan moved off the rack to make room for my '59 Kodiak. I miss the '58 Alaskan more. The '58 Grizz had the same glass as the '58 Alaskan - love the'58 Grizz
The Alaskan was introduced in '58. That's also the year the Grizzly was redesigned from a static recurve reflexed at the handle to a recurve with deflexed riser. Everything was completely redesigned for '59.