Dicks had a meltdown, for good reason.

[onlinebiker]

They pledged to destroy the firearm in accordance to federal guidelines which means all they need to is cut or smash the lower receiver.

rollingstone.com/politics/politics-features/how-to-destroy-an-ar-15-629272/

According to the article, 'cut or smash' isn't good enough.  This section of the weapon must cut into 4 pieces with a cutting torch.  I'm not by any means a firearms expert, but it seems that subjecting the item to that much repeated heat would pretty well ruin it (at least as far as repair or rebuilding goes).
Could be wrong, though.
Boru

Dirch is spot on.

A "firearm" is the lower reciever block that has the serial numbers.

This is how they got around the Clinton AWB. They destroyed the reciever and brought all other parts into the US - then reassembled with just enough American made parts to be legal.  CAI did a shitload of FN-FALs and CETMEs this way.

I would not be surprised to see some "parts kits" coming onto the market.