Free: Contests & Raffles.
Not including the flight up to Fairbanks, With renting a raft from the flying service it would be in the area of $1,800 a piece. That's 2 people and 100 lbs of stuff per person. That way it is cheaper and he only has to take one trip out. Multiple trips increases the cost. The Kongakut is one of the most scenic remote rivers in Ak. I have never done a float that far north in Ak or in ANWR for that matter.
Maybe when you add the word "sheep" to your plans, the price goes up.Pretty sure it won't be Sky's 1st time in a bush plane in AK.