You might also try the Western Wood Production Association. http://www.wwpa.org/about_wwpa.htm They say they service Alaska, but I didn't see any mills.

One final thought...contact the closest lumber mill in your area and ask who they use for grading, or, if it's in-house, if you could hire somebody to grade your timbers.

Around here, graders sometimes do work on the side.

Good luck!
-srj