Link to the website is here. The website is basically a Taiwanese version of eBay. So is it a fake?
(And a side question: would this be an upgrade from my Superlux HD668b?)
They are 100% fake. The Sony logo on the pouch is the main detail where you can see that it's not an original. It should be white and printed instead of black and pressed. The ear pads seem to be cheaply made and the headband stitching looks bad as well. The "For Digital" sticker looks wrong, the text should be at the bottom of the sticker and not at the top.
To me, it's really hard to tell. I am a V6 lover and I never found anything cheaper that did such a good job. Besides the V4 maybe which is an older model and is open anyway. You can definitely find some used but real V6s on Ebay for about $50. You'll be more than happy with these. If you have a doubt about any counterfeit headphones on an auction I'll be glad to help you out.