You'll never haul an elk + camp out in 1 trip, with 2 guys, 5-8 miles in. Not legally anyways.
Here are some averages on elk quarters from a butcher shop:
front quarter bone in - 36 lbs
front quarter boned out - 28 lbs
hind quarter bone in - 66 lbs
hind quarter boned out - 58 lbs
Misc (neck...