So I don't know the details, but YSL limits its distribution of many of its fragrances. If you live in a big city, you can see if they have a YSL Boutique and check out the whole line there.
If not, on ebay you can get M7 for about $25 including shipping (def under $30).
M7 Fresh is much harder to find, you might want to start with buying a decant off of a basenotes member 1st on that one. On ebay, expect to pay minimum $50 for it, and that's only if you are lucky enough to find it.