I just recieved a set I bought on ebay ($299.00). I am pretty sure they are comming from the same manufaturing source as Mopar Performance so as far as I know there is only one reproduction, just being sold and marketed by various vendors.
They are not all that accurate IMO so if you care about OE type details you'll want to find originals.
Here are the most obvious issues I noticed:
#1. The overall stampings are sharper/crisper in the transition areas, these will be obvious at a glance to anyone familiar with them.
#2. The flat surface with the plug holes is too smooth, basically 100% flat where as originals had ripples/rings that were around each plug hole, again, obvious to the trained eye.
#3. The spark plug wire retention bracket feet where they contact the cover surface are not as wide as originals, a very obvious measurable difference.
#4. The 3 passenger side wire loom retention bendable tabs lack the dip coating.
#5. The single drivers side solenoid wire bendable tab lacks rubber coating.
#6. The plug tube recess holes are slightly smaller than original, when installing an original tube and O-ring seal the O-rings don't want to go down into the holes as they should, instead they hang up on the upper edge and start pulling the surface of the cover inward oil canning it down with very little pressure, I believe the lack of ripples in the flat upper surface stamping makes it weaker and causes the oil canning to happen easier, at any rate something is different because they bend inward way easier than originals.
#7. This one's a big deal IMO, the passenger side oil fill cap twists in and seats in the wrong position! They clocked the hole notchouts in the wrong areas so rather than the caps two ears pointing towards the front and rear of the car when tight (3 & 9 o'clock), they instead point at about 2 & 8 o'clock!
So, bottom line, they can be made to fit and function, and they look ok, but "correct", they are far from it.