I'm not really familiar with made-in-Italy boots (if Coach did/does make them there) but I don't want to appear to ignore your request. I'm a bit baffled and at this point and I don't know whether they're authentic or not.
While the font on the Coach name on the sole looks okay, I'm not familiar with Coach having a lozenge stamp inside the boot as well as so little other information inside.
Every pair of boots, sneakers, sandals and shoes I've seen has had more information on the inside. There's usually a style number, style name, "made in" country and size information. Sometimes there's also information about the construction material.
Your boot appears to only have what looks like a style number, European size and the Coach lozenge. The font on your boot is different from what I'm familiar with but it could be because they're Italian-made. Are there any more markings on the inside?
Is there anything on the insole? It might be hard to get a photo but the counterfeiters often have trouble (or make no attempt to) getting it right on the insole.
If you can't get a definitive answer here, you might want to post your question and pics on the shoe forum. Dallas is very knowledgable re shoes but I don't know how familiar she is with Coach: http://forum.purseblog.com/the-glass-slipper/authenticate-those-shoes-32044-270.html#post17922954
If you want, you can cross-reference this post in case she wants to read another opinion.
Sorry I can't be much more help.
The very inside sole has no markings, but I'm not sure if it's because there is no zipper & not the easiest to get to??? The bottom sole feels like my other Coach shoes but just not sure on these.......I posted over in shoes as well.