Build almost complete just missing a PSU and a Case.

Hey guys.

So this is my build thus far:

Mobo: ASRock Z77 Extreme4. Picked this because from what I read it's the best bang for the buck out there at the moment. It seems recent and compatible with the rest of my hardware.

CPU: i5 3750k. Very good reviews. Was on the verge of swapping it out for an AMD FX 8350 but it turns out it's only better for streaming (which I never do and don't plan on doing at the moment). I'm more comfortable with the i5 3750k with my budget and all the positive reviews I've read about it.

CPU Heatsink: COOLER MASTER Hyper 212 EVO. Very favorable reviews and very nice price.

GPU: GIGABYTE GTX 670 Windforcex3. Reliable and very good reviews on its cooling.

RAM: G.SKILL Ripjaws Series 8GB. From what I learned going with 2x4GB is better than 1x8GB to make use of the dual-channel. Picked this over a Corsair Vengeance because of more reviews and recommendations.

Internal HDD: Western Digital WD Blue 500GB. I'm really trying to cut down on costs because of my tight budget. 500GB will do just fine for me and I decided to get an SSD some other time. I simply cannot afford one right now.

Optical Disk: Gonna use an old one from my old computer since I almost never use this anyways.

So as you can see the only 2 things I'm missing are the PSU and the case. I have no idea which ones to get because of the huge selection but just to make something clear regarding the case I DO NOT GIVE 2 SHITS ABOUT HOW IT LOOKS. I just really need to cut down on costs so the best reasonably priced ***-looking case that's compatible with my build will do. Preferably something with those trays that let you easily install HDDs. Quality is very important for me even if something is a bit pricey and is missing some features but has good quality and reliability I'd choose it over a cheap product with more features.

I have a question about PSUs though. Which of the 80+ ratings are recommended and which are overkill? Is an 80+ Titanium overkill for example? Is a Bronze enough or would going for Gold be optimal?

Not sure how much watts I'd need for my build but I'm guessing around 650 sounds about right.

Budget: ~$1200 can go a bit more
Resolution: 1920x1080 single-display not planning to ever go double-monitors or more.
Games / Settings Desired: Mostly Guild Wars 2/WoW/Planetside 2/Bioshock Infinite/Farcry 3/Dishonored/L4D2/Borderlands 2 etc. I'm hoping to play most titles going out this year on High if possible (not Ultra.)
Any other intensive software or special things you do (Frequent video encoding, 3D modeling, etc): Fraps perhaps and a bit of streaming but these aren't so important. I'm on a budget so can't be picky.
Country: I live in Kuwait in the Middle-East but will probably be ordering from a US website and have it shipped to an American friend of mine who will ship it here.
Parts that can be reused: None.
Do you need an OS?: Nope. Already have Windows 7 Home Premium
Do you need peripherals (e.g. monitor, mouse, keyboard, speakers, etc)?: Nope. Already have all the peripherals. Just missing a PSU and case.

System Usage from Most to Least Important: Gaming (%98), Fraps (%1), Streaming (%1)
Preferred Website(s) for Parts: newegg.com, amazon.com
And Most Importantly, Why Are You Upgrading: I have a very old computer (has a GT 9500 card lol). I'm building a new one so I'm able to play most titles this year at High settings (not aiming for Ultra because of tight budget).

Could really appreciate your help. Thanks