Should I contact faculty for RA positions

[Cnk17]

So, I've recently been accepted to a Public school for MS Biostatistics. I've not been contacted by Department regarding financial aid so I'm assuming I'm not getting any since it is rare for MS applicants. 

I'm an international student and this is my second masters( I have a master's in Statistics/ I wasn't eligible for graduate program due to three year undergraduate course). So, I  need some kind of financial aid. I've read on some forums that RA positions are under professors and one should contact faculty before/ after acceptance.

Is this a commonly followed method in Biostatistics programs.Should I contact all the relevant faculty or talk to graduate students first( through LinkedIn) and then approach.

I've experience as RA and tbh considering the subjects I've studied, I can also be a TA( I've good speaking TOEFL score).

Any kind of suggestions are very much appreciated.

Thank you