With the $30 you save you could invest in some higher CMF fans to throw on it to make it even better.
If you wanted to up your budget to about $70-$100 then there are some other options from Zalman, Xigmatek, or some of the more expensive Cooler Masters that you could look into but typically the 212+ is the "go to" budget HSF.
I have not had much personal experience with overclocking a i7 2700k, but i would assume you could probably get it up to around 4.5Ghz - 5 Ghz, but that is just a guess based on how much most people on these forums overclock their 2500K.
I would recommend getting a quality water cooling solution if you would plan to go any higher than that.
Side question answer: No!
the stock HSF on the GTX 680 (or any graphics card really) will be sufficient.
Typically the only time that you need to worry about adding extra cooling to your graphics card is if you deal it some heavy overclocking, or you are running multiple in a smaller case.
There is no answer to how high you can overclock because every chip is different. No two 2700k's will perform the same, they are all garunteed to work at 3.5ghz minimum but their overclock potential is different as every piece of hardware is different. It also depends on motherboard. You should not need cooling for your 680 if you have a case with decent ventilation.
The NZT Phantom 410 is a mid-tower pc case that is 215mm wide. A 120mm tall cpu heatsink will fit without any problem. The best value is the Cooler Master Hyper 212 series that others have mentioned. Over the years Cooler Master has introduced several variations. I have the original Hyper 212 in my personal pc. It still works for me.
Last month Tom's Hardware published a review of 14 CPU Heatsinks which included the Cooler Master Hyper 212 EVO. Here is a link to the article: