Could be that they are the real deal that's why Merc. isn't going after them. Dale Wilch has a pretty good reputation in the HP car stuff. He wouldn't carry them if they were junk. I would go for them. I have always used the Crane golds nut if I needed a set I would get these. Just my .02.

If they were fakes(I know plenty out there) I also think merc would be all over them, especially with a part # on them..

You think Mercury is trolling Ebay for this. I doubt it. I'm sure they wouldn't care either. The market is certainly not flooded with them.
Either way I am not buying them. Not worth the risk. Crane golds are proven to be worthy so....

From Merc..
 

So I contacted Mercury and this was the final responce I got.
"Here is an update. According to our engineering dept - the current design no longer have any logo on them. The e-bay ad is ligit; they are old stock 520/540/565 parts. Atlas is not the manufacturer, however. Scorpion Racing Products is. The -C indicates Rev C, which went away in 2010. 600/700 use a different design, which I believe still has Mercury lettering on it."

That being said, They do look just like the scorpion endurance series rocker. Attachment 575447

So... I bought a set..
 

And IMO there some really nice parts. No play in the bearings.
The pics shown in the listing makes them look porous and roughly finished.
There not at all. There machined billet parts as the listing says.
Definitely an upgrade from the Crane Energizers I took out..https://cimg7.ibsrv.net/gimg/www.off...ec08eb17cc.jpg
https://cimg8.ibsrv.net/gimg/www.off...1281895a54.jpg
https://cimg2.ibsrv.net/gimg/www.off...8a3f369698.jpg

I vote for Chinese garbage, with the savings you can put some slick 50 motor oil additive and it will give you 40 hp extra.