It is unfortunate that they are no longer on that campus.
I recommend contacting the university to see if they have any records of ANYTHING pertaining to the organization or some of the members whose names you remember.
I assume it was a local so there wouldn't be a larger entity to contact. (There's another Sigma Phi Nu that was founded in 1996)
"It takes two to make a thing go right. It takes two to make it outta sight."
~ Lyn Collins
"I'm good. I'm really good. I know you don't think that I am. But I'm good....life happens, when unexpected things happen just say 'plot twist' and move on." ~ Jordan Sparks