One of my rifles, the lightest one, that I also intended as a sheep/backpack rifle has a 3-12x42 Huskemaw
on it. That scope is also right-in-there for your weight considerations* I like mine alot. Great hunting-scope, not bulky or heavy by any means and fit my "weight/size/value" pre-requisits when I was choosing..
They actually offer a 4-16 now in the same housing as the 3-12.. I'm sure that extra magnification wouldn't add all that much extra weight (if any) Definitely gain a bit more mag-power which can be handy
(Personally) I think the Husky takes the cake for this purpose vs Leupold or Vortex.. but that is only an opinion, I won't get into it. Buy which you like best above all else, but I strongly reccommend taking a look at the Huskemaws. This category is where they shine.