I'm sure a lot of you are aware of it, but for those who aren't I'll just mention this. One of the best game bags around is military surplus mattress covers. You know, the old "Fart Sack" of days long ago.;)
They'll last a lifetime if you wash them once in a while. And, at times I've seen them advertised as low as 3 for $15.00. One works very well for Deer, and four will take care of your Elk. Easy to close at the top. We use clothespins and maybe some twine.