for 300 you can get Cambridge audio 350a. It is discontinued. It used to be $500.00 they sell it and some amazon.com people are selling it for that price. http://www.hideflifestyle.com/
How many watts are you looking for? You can get a NAD 40 watt amp c326bee for $380.00 It doesn't have pre outs or a subwoofer output though. the Nad c326bee is $550.00. It has pre out and I think two subwoofer outputs. I will check and see if I can find any more amps for $300.00.
I looked at the Marantz as well, but it was a little too expensive for me. I found an HK 3490 on craigslist new for $260. J&R has them in stock right now for $449, but if you call they will give you a better price. They just can't advertise the price online. I love my 3490. If the 3490 is too expensive and you don't need the Digital inputs, then go for the 3390.