You are wrong, all the receiver's were identical internally, all showing the same welds, the first four that were submitted to the RCMP had the same welds. Not the first time the RCMP have changed their minds. This is all history now, the debate is long over.
There are many other firearms in Canada where the receivers are identical between prohibited and non prohibited models, some of these sell for several thousand dollars each but I am not about to list them here!