Three things shout "fake" to me about the "sunplosion" listing.
The first is that the shadow compact is wrong. It's little things like the way the clear insert attaches to the lid, the shape of the catch and the shape of the lower half of the compact that mates with the lid. I've tried to take a photo of a genuine shadow (it's Trax so the colour is different!) and put it alongside the eBay listed picture so you can compare a fake and a genuine compact.
The second indication is the fact that the shade is identified by a number. The only M·A·C products identified by numbers are their brushes. If someone claims an eyeshadow is a #14 or a #7 or a #
anything it's a sure sign it's a fake. There
are three character "numbers" on M·A·C products which sometimes people confuse with shade codes but these are batch identifiers. You can read about how these codes work
here
The third is the claim made in the answer to a question about the origin of the shadows. The seller claims it came from Europe but it makes no sense for a Canadian to buy M·A·C shadows in Europe as they are much more expensive over here (of course if a product is sold out it
may be worth it). In the UK a single eye shadow costs CA$20.10 compared to a price of CA$16 in Canada. In France the price us CA$18.35.