I wouldn’t be surprised if NSA purchased equipment using a method akin to greymarketing where the supplier either

A) doesn’t know the true destination of the parts, including purchases through an agency other than NSA, or purchase by multiple “individuals”

B) NSA has arrangements to compensate manufacturers using black budget line items and gov projects line items where disclosure of the production or even something like funding of a stand-up of a factory is not clearly delineated or otherwise inaccurately designated in SEC and IRS filings. More so I’m pretty sure there is a named procedure/process and maybe even a working group or sub-unit, similarly bearing a unique cryptonym, enabling the large scale acquisition of goods while keeping the regular record publication flows ignorant.