IS 500w Enough?

So this year I am upgrading my PC. Currently the specs are - AMD Phenom II x4 965 - EVGA GTX 650 2gb Superclocked - ASRock 770iCafe AM3+ Motherboard - 2 SATA HDDs - 1 SATA DVD Drive - 3 fans (includes CPU fan) - 500w Cooler Master PSU. I have seen mixed statements all over the internet, so I turn to here. I am upgrading to an ASUS GTX 760 and adding a 2tb HDD and some places say that these specs will exceed my 500w PSU's capabilities while others say the least I will need with these specs is 400w. I would just like a straight answer, do I need to get a new power supply? I would prefer not as I can only spare $80 right now. If I do need a new PSU, could anyone recommend a good one say, 600w, 650w or 750w for under $80? Thanks in advance.

500w should be enough, but what model of cooler master is it? Some are very poor quality.

It is a Cooler Master eXtreme Power Plus 500w. I have been using it for almost exactly 1 year and have had no problems with it.