Have you looked a Boyd Laminated stocks? They are wood but almost impervious to weather.
LOVE Boyds stocks. Theyre priced right, and are built like tanks.... Theyre not what I'd want on a "mountain" gun (heavy).. but theyre about perfect for 90% of the hunting I typically do..
I've got 2x .308's, a 7x57, a .35 whelen, and a 7MM WSM all wrapped in Boyds laminates....
When I build my .458 win mag, it will get a boyds stock as well..