I remember several mods of r/darknetmarkets posting that they received NSL's forwarded from actual reddit admins.. Not sure if that post is still available though.
Yes, but they still could have been accompanied by gag orders despite not being a NSL. There are several categories of administrative subpoenas which can have them, and which could have been plausibly used in my case - the financial ones, for example, due to the Bitcoin/money laundering nexus.