You'll get lots of recommendations, but I'm gonna suggest a Weaver Grand Slam, in either 4.5x14x40 or 6x20x40.
For the money--$335 or so--I don't think you can do better. It's not a tactical scope, so don't expect 1" high target turrets or a mil dot...but since you said it's a hunting scope, I don't think you need them.
I have this scope, and it's a very solid. Very clear and bright glass, and the POI is consistent throughout the power band.
They have lesser power than those two, if you don't need the extra X.
Here's a quick pick of some scoped ARs of mine, but the Grand Slam is on my .22-250. What you're looking at from front to back is a Super Sniper 10x, a Burris 3x9, and a Nikon Buckmaster.
If you want something more military looking, and want to drop down the power, you might look at some IORs, some of the Leupolds and other similar stuff.