I would definitely NOT go with a 7970. That card is outdated, and prices way too expensive for its performance. In all honesty I would go for a cheaper MOBO (any basic X79 will do, try the ASUS X79 deluxe) and spend the extra money to get a TITAN BLACK as it will be unbelievably more powerful...
I would go with a Corsair Vengeance headset, either the V2100 if you want wireless, or the 1500V2 if you want wired. They both are the same besides wired/wireless.
I do not personally have any experience with Origin, but I have a friend who had his PC built by them. It was a pretty high end rig, with a 3930k, Rampage IV Extreme, and GTX 690 all with custom watercooling and he hasn't had a single issue.
Here ya go, Tom's even did a review of it as well: http://www.eurocom.com/products/
http://www.tomshardware.com/reviews/eurocom-panther-5d-notebook-review,3685.html
If you spend a lot of time gaming then the laptop with the i5 and more RAM will definitely be worth it, although you will have to play on lower settings due to your GPU.