"...because it was not specifically named..." A firearm doesn't have to be specifically named to be declared evil.
The MP7 is evil because of its OAL and barrel length. OAL 23.23". Barrel length 7.09". That says restricted to me, but the idiots in Ottawa don't listen to me. If there are any here at all, it's most likely considered an MP5 variant and therefore prohibited.
You wouldn't likely be able to fiind ammo or brass if you could find an MP7, anyway. MP7 comes in 4.6mm x 30mm only. MP5's are 9mm.