Mac Style Snob is an LE item, unfortunately, and you may be able to find it at a CCO, but chances are small since it was a pretty popular color (though it doesn't hurt to check).
Burberry Rosewood is about the same intensity, though it doesn't seem to have the slight pinkish undertone that Style Snob and Sidecar have. Here are some swatches:http://www.google.com/search?sourceid=c ... y+rosewood
Of course, swatches change based on skin tone, so you may find that it's close enough for your purposes.
Rosewood is much more expensive ($29 for 0.088 oz), but the Ebay listings for Style Snob are about the same, at the moment (~$28 for 0.05 oz). Reviews of the Burberry line have said that the shadows are pretty good, though I can't speak from personal experience. In the end, though, I guess it doesn't help much if you're paying $30 for one eyeshadow instead of $50 for a whole new Naked palette.
Here are also some additional dupe ideas for Style Snob:http://www.thebeautylookbook.com/2009/0 ... isons.html