Yea I've been reading it, and there isn't any real acceptions. The Jing Gong has crossed the border a few times, because its not readily identifiable as a real firearm from any distance.
55. Except for replica frames and receivers, most parts intended for replica firearms will generally be admissible, subject to other customs requirements such as payment of duties and taxes. However, border services officer must be vigilant that the parts in question are not interchangeable with real firearms or are not prohibited devices in their own right. For example: border services officer must ensure that the magazines that come with replicas are not real magazines that can be used in firearms and be able to store real ammunition.
Still no frames and receivers ever coming through, and no guns (other than those apparently looking like sci-fi toys)
are getting in.
Maybe one day that will change.. lol. I made a funny. ;P