These are older than 25 years now.  I know the odds of a finding well functioning 1984-5 are pretty slim.  Would it even be worth undertaking?  
I assume you’re looking at similar requirements to the old defenders. Requirements so prohibitive you’re better off buying one of the handful of NAS defenders already here.
	
			
			I assume you’re looking at similar requirements to the old defenders. Requirements so prohibitive you’re better off buying one of the handful of NAS defenders already here.