Free: Contests & Raffles.
Bullpacs, bar none .IMO
Cabela's outfitter frame has worked just fine for me. Packed a lot of quarters out with it plus countless trips of alfalfa and bags of feed.
^^ive got two exclusively for packing critters out. Comfortable and light. Can take a heavy load.
Kifaru
If you want a really high quality pack that will be fairly light but be a breeze to carry, check out Exo, Kifaru, Stone Glacier or Mystery Ranch. I’ve heard good and bad about Kuiu. If you hunt close to a camp and don’t want to shell out much money, any of the frame packs mentioned will work. They won’t be as comfortable, but that does not matter much if the pack out is short.