I've had both Apex and Cobra sights, both are very good sights.
I have to agree with TheBigSky also, I have a Montana Black Gold Flash Point also and I love it. I also shoot a Spott Hogg SDP (7 deadly pins) and like that sight a lot also, however for most applications 7 pins (20-80 yards) is pretty unreasonable, the SDP is also over your price range. But SH makes several other 3 and 5 pin sights that will fit your budget.
Another Great Sight is Toxonics Brand, and even their most expensive sight is not much out of your budget... you get a lot of good quality and features for less $ with them. If I were in the market for another sight I personally would give them some real consideration.
http://www.basinarcheryshop.com/ This sight has an awesome selection too, and very reasonable prices. you can look sights up by price range too.
Something else to look for is get the smallest pin diameter you can. like .019 or .010 size; the larger dimaeter pin sizes (.029) block out more of the target area, and thus are less accurate.
