The Loupold Mark IV is pricey (about $1200) but the SFWA SS on the green rifle is a great scope for $299-$399. We've accomplished groups of .247" at 100 yards and killed one gallon jugs from 950 yards with it.
Here's where you can find them: http://swfa-ss.com/
Some people call a piece of junk but I've never actually found a bad review on it. Everyone says it's equal to any scope four times the price!