Someone there will help you with it and tell you if it's fake or not. I'm not sure if model is on the Coach website or not but if it is, you could look it up and they have this button "try it on" where you can select your height and it'll show you a model size version of a person your size with the bag so you can tell before you buy it. If it's not the latest, then ask for measurements and compare.
I've seen that model before, or one just like it, a few years back. I've got it in the smaller size in black satin, thanks to the outlet. I'd be surprised if it was still on the website but it might be in the drilldown, if you can get the item number.