A "disguised knife" in most its forms are ILLEGAL in most states ... I'm not sure where they ARE legal, but I imagine there has to a be a few places where people can legally buy knives that hide in keys and pens.
As for the knives you pictured, I'd say they are perfectly fine as long as they open by being bulled or the use of a thumb stud (i.e. they do not open by a spring loaded mechanism or gravity). But then, I'm not in NY so I can't say whether the statutes have been modified by case law in any way or not.
Contact your local police department or an attorney.
I can't see where buying a pocket knife should be that big a deal. Are you planning to get in to a knife fight? Why do you need one?
- Carl

