You don't need an i7 to run games well. i7 doesn't really improve gaming performance, and is more for stuff like hardcore video editing. An i5 will be more than enough. I would get a socket 1150 mobo and a newer i5 processor, and you could probably still get the nice graphics card.
I would say just start fresh. 4670k, z87 mobo, you know everything. You could possibly buy a 1366 processor and overclock it. But if you are going to go with a socket 1366 processor get an overclockable I7 it will last you the longest in terms of gaming performance for that socket.