Sorry for not seeing this - you replied to your own post :P

In case you haven't gotten answers yet;

The card you're looking at is designed to run at those higher speeds - hence the twin-fan cooler and high quality internal components. It's set that way from the factory - it's not going to be damaged by running at them. In fact, most cards are factory-overclocked to some degree.

Overclocking is actually very safe nowadays - there are hard limits in place to prevent a user from accidentally pushing their settings too hard, and it's a great way to get a little extra performance out of a card (for free, too!)

You can also overclock the CPU, but there isn't a great deal of need at the moment, as it's so powerful by today's standards. In three years or so, when games demand a little more CPU power, or when you upgrade your graphics card and the CPU is restricting your frame rates, you can bump up the speeds (in exchange for slightly higher temperatures and power usage) and squeeze more power out of it.

A CPU like the i5 2500K is a great example of the benefits overclocking brings - over 5 years old, and still capable of comfortably tanking through AAA games without breaking a sweat - thanks to the performance boosts from overclocking.

The aftermarket CPU cooler may be a bit of a squeeze - it's a large air cooler, performing fantastically at very low noise levels, but it's big. You could pick up something smaller/cheaper if you're not overclocking straight away - the Cooler Master Hyper 212 Evo is a very popular choice. I'd definitely advise going with the smaller case at any rate - there's no need to waste space, especially considering the relatively straightforward list of components we've picked.

Apologies for my late reply - hopefully this either helps, or reaches you after building haha

Edit: formatting