OK your looking for a gp optical sight for your AR.
General plinking at the range can be satified but many optics. I am sure you don't want a scope mine what I have hanging out on top of my AR (Nikon Monarch 6-24x50mm). A 1-4x will give you a great FOV at 100 yards. But will really hinder your shooting past 100 yards.
I would say go with a nice 2-7, 3-9, 4-12x scope in your price range you can get some great optics in that power range. I would look at SWFA tactical Rings or Burris. and forget the riser. Tall rings will get you where you need to be as far as height of optics. You want them about 1" to 1.5" off hand guard. give or take.
Try optics planet Great people to deal with.
Here is a set up Burris rings and a Sightron SII Big Sky 3.5-10x40mm $500.79 I know I blew your budget but I think .79 cents wasn't to bad.
Here is another set up that saves you some money. A Nikon 223 scope designed for the AR-15 and the burris rings.