Why not call Vector and ask them for whatever ATF letter they have on file? I have a hard time believing that they would endanger their FFL by selling illegal guns.
But I suppose if one was really worrying over it they could take their folding stock to a welding shop and have it welded open.
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In a few years when the dust finally clears and people start counting their change there is a pretty good chance that President Obama may become known as The Great
Absquatulator. You heard it first here on TFL.