Can I print and sell 3D models licensed under CC BY-NC-SA 3.0
I am not an attorney, so this isn't legal advice. Like any legal question, you should consult with an actual attorney, who can consider all the gory details.

That said, it seems like you've got the BY and SA parts covered. "Non-commercial" is more difficult: does a sale that's not for profit count as "commercial"? 

The Creative Commons site (https://creativecommons.org/faq/#does-my-use-violate-the-noncommercial-clause-of-the-licenses) explains it a bit more, as pasted below. But perhaps the best thing is to just drop an email to the originator and ask. Probably you'll get an email back saying it's fine; and who knows, maybe you'll make a new friend, too. I've been on both ends of exchanges like that, and it's generally worked just fine.


  Does my use violate the NonCommercial clause of the licenses?
  
  CC's NonCommercial (NC) licenses prohibit uses that are "primarily
  intended for or directed toward commercial advantage or monetary
  compensation." This is intended to capture the intention of the
  NC-using community without placing detailed restrictions that are
  either too broad or too narrow. Please note that CC's definition does
  not turn on the type of user: if you are a nonprofit or charitable
  organization, your use of an NC-licensed work could still run afoul of
  the NC restriction, and if you are a for-profit entity, your use of an
  NC-licensed work does not necessarily mean you have violated the term.
  Whether a use is commercial will depend on the specifics of the
  situation and the intentions of the user.
  
  In CC's experience, it is usually relatively easy to determine whether
  a use is permitted, and known conflicts are relatively few considering
  the popularity of the NC licenses. However, there will always be uses
  that are challenging to categorize as commercial or noncommercial. CC
  cannot advise you on what is and is not commercial use. If you are
  unsure, you should either contact the rights holder for clarification,
  or search for works that permit commercial uses.
  
  CC has a brief guide to interpretation of the NC license that goes
  into more detail about the meaning of the NC license and some key
  points to pay attention to. Additionally, in 2008, Creative Commons
  published results from a survey on meanings of commercial and
  noncommercial use generally. Note that the results of the study are
  not intended to serve as CC's official interpretation of what is and
  is not commercial use under our licenses, and the results should not
  be relied upon as such.