Professional References

I have an interview on Friday and I was told to bring in 3 professional references (someone I have worked for....supervisors/managers). I have two professional references that I can definitely use (my current manager and previous manager) but I don't know what to do for the third. Could I use two different people from the same job? Could I use a clinical instructor? What do nurses who have never worked before do about professional references? I have worked at multiple jobs but some of them were over 7 years ago (and I don't really want to use them anyway). Thanks for any help!
You can use a clinical instructor as your third reference.
Could a former co-worker also act as a professional reference? Reason I ask is because my last supervisor was from a position five years ago. I am having a difficult time reaching him on a consistent basis, and my last message from him was, "Who are you again?"
You can list someone who was in a charge nurse/ supervisory type role. I have agreed to do this for some of my coworkers but am sure to say that I'm not responsible for reviews, but I can refer them as a peer.
Thank you.