(a) No person shall knowingly transport, ship, possess or receive any firearm or firearm frame or receiver with the knowledge that the importer's or manufacturer's serial number has been removed, obliterated or altered in a manner that has disguised or concealed the identity or origin of the firearm.
(b) This section shall not apply to a firearm manufactured prior to 1973.
(c) Possessing, transporting, shipping or receiving a firearm with a removed, obliterated or altered serial number pursuant to this section is a class D felony.