I just bought a Behr (original equipment) radiator from autopartswarehouse.com last week. Ordered it Friday night & it was on my doorstep the next monday night, free shipping. The radiator was under $300. But of course any additional parts (radiator hoses, coolant, etc.) are additional.
It is pretty easy to replace though, as radiators go.
But you did have one poster that said the bar leak type stuff has worked for him for 15,000 miles.