1- Yeah, the PSU is Seasonic (a very good manufacturer) and you won't have problems.
2- Your wallet
3- Those looks good, but if you can go with this: http://www.newegg.com/Product/Product.aspx?Item=N82E16820233144
4- Anti static strap, patience and some screw drivers for install the cooler and PSU
5- Not now, if you have too much noise a fan controller in future is a good option
I forgot to mention I will be using two
(updated now) of those video cards. Is my setup still sufficient? PSU, case, MB?
Also the MB is out of stock(or so they say for the combo deal). Could you suggest a reliable replacement with a usb 3.0 header?
Thank you for your quick, helpful reply.