Fleece Pants for insulation layer?

[InteriorAKPopsicle]

I'm doing an October Sheep Hunt in Alaska and I'm looking for the best "cheap" option for my insulation layer. I was looking for military surplus pants and came across some fleece pants.

I'm currently running the following:
Black Ovis Merino Boxer Brief
Black Ovis NWT 250G Base
Stone Glacier De Havilland Pant
Insulation - was thinking a Fleece Sweat Pant
Rain Layer (looking for camo suggestions - considering FirstLite or one of the other brands)
Costco 100% Merino Wool Socks and REI Liners.

Top I have:
Black Ovis tShirt
Black Ovis NWT 250G Merino (hooded)
Frontier Gear Fleece Lined Wool QuarterZip (Barney's Sports Chalet - Anc Wooly Mammoth)
Insulation - Eddie Bauer 750 Fill Down Coat
Rain - currently camo Military Surplus but thinking about getting something to match the pants I need to buy.