I never saw a fake that had DJI written on them, but I'm no fake prop expert. I did get some brand-x CF props off eBay, and after a load of balancing they are holding up very nice and perform great. Whatever you get, I'd balance before using. There are some that say you don't need to balance, but after 30+ years of r/c hobby, I say you do.
Never heard of these props and, though the photo shows 5 pairs of greenish-gray props, the descriptions says "CW/CCW 1 Pair Black Props." If its one pair for $19.84 it isn't even a good deal.