Hmmm.... I'm not that aware of the prices on the American/Canadian market, since I don't live in those parts! However, I'll give you a few examples of acceptable monitors for the purpose specified!
For a gaming monitor, you need to be particularly aware of the following:
The monitors refresh rate: The Lower the better (I would say max 8-12ms for a gaming Monitor)
The monitors contrast ratio: This is important if you want the best viewing experience from your movies and games. The larger the color contrast, the better (Atleast 700:1 for a gaming monitor at that price range)
The monitors brigthness: Also an important feature. Would recommend 300cd/m^2 or higher
The monitors video bandwidth: Somewhere around 150mhz and above should be acceptable.
Here are a few examples, however do note that when buying a monitor you'll also need to buy an external TV tuner for it. You could possibly set your PC up as a Media Center, or simply buy a TV Tuner box in order to watch TV on it. Also be sure that your Graphics Card is capable of handling the Native resolution of the monitor you want to aqquire!
http://www.benq.com/products/LCD/?product=838&page=specifications Price here in Denmark is about 336,86 $ (including the 25% VAT we pay here)
http://www.asus.com/products.aspxl1=10&l2=89&l3=362&l4=0&model=1741&modelmenu=2 Price here in Denmark is about 331,37 $ (including the 25% VAT)
http://www.samsung.com/us/consumer/detail/spec.do?group=computersperipherals&type=monitors&subtype=lcd&model_cd=LS22PEBSFV/XAA&fullspec=F Price here in Denmark is about 401,57 $ (including the 25% VAT)
My personal favorite is the Samsung one [Last one], definately well worth the money, despite it being slightly more expensive compared to the other two!
Hope this cleared up a few things for you!
NOTE: Of course you could always buy this one, once it comes out
https://www.youtube.com/watch?v=2yT6OuGXmGo