As mentioned above already, there a some very good options out there, with weight and quality of glass being most important on a sheep rifle.
We hear lots about the long range shots on sheep, but in reality, there are more sheep shot within reasonable distances, and you have already stipulated your range limit. My longest shot on sheep to date has been 300 yards (all others less than 180 yards), and just 110 yards for mountain goat (the others were shot within bow range).
Pick the magnification range that will get you the scope you will be happy with for that maximum distance, but still be able to dial down for shorter distances While various manufacturers make great glass in the magnification ranges you will decide on, watch their weights as they can vary significantly. I was interested in a particular product until I found out that the scope weighed 29 ounces! Swarovski makes some great scopes that are fairly lightweight (approx. 1 pound), as does Leupold. I also like Trijicon, but am not up on their newer products.
The rifles I use for my mountain hunts all wear Leupolds; mostly for their weight, quality of glass and reticle options, and lastly affordability. I have VX-3's in 2.5-8x36, 3.5-10x40, 3.4-14x40 and VX-5HD's in 3.5-15x44 and a VX-6HD 2-13x42, all w/ B&C reticles. Todate they have all performed well, and the only one I have had to send back for service was the one where I slipped and fell, with the scope hitting the rocks first. I mailed it to Korth, they repaired the scope and mailed it bac to me and it was back on my rifle in 11 days! (Warranty and customer service is another consideration I did not cover above) As may be evident by my scope choices and field experience, I am a hunter first and prefer SFP scopes. I also like the simplicity and speed if use of the B&C reticles (no need to take extra time to dial), but this is my preference. My binos are RF too for this reason.