A Leupold, Vortex, or Burris 3x9 would be just fine. You might like the Burris Ballistic-plex that will help with going out to longer distances, they make one specifically for 223 and it's pretty well reviewed. Some folks prefer to do click adjustments, but personally I like having a not too busy reticle that will help you get on target at longer ranges. Personally I've got scopes that range in price from about $100 (for my 22) one up to about $1400 (Bushnell HDMR for long range)
Here's the Burris:
https://www.amazon.com/Burris-200137-MS ... th=1&psc=1
I've got a zero magnification Vortex and like it a lot. For your purposes, this would probably be the one:
http://www.primaryarms.com/vortex-cross ... -cf2-31007
What do you get for more cash? Brighter, better eye relief, more positive clicks on the turrets, overall better glass. You can spend a ton, but hell, my $180 Nikon is still a damned fine scope. For a first scope either of the two above would do you just fine.
“Do the best you can until you know better. Then when you know better, do better.”
- Maya Angelou