What do I tell SARS if I can't get my IRP5?

I used to work for retail when I was a student and worked some weekends got paid differnt amounts depending on my days worked ranging from R200 to R450 a week but I did not get a payslip, now SARS is asking for an IRP5 for 2012 when I was working there. I can't get any thing as I was not getting a payslip I even have no proof that I worked there.

You will need to go into a police station and put this in an affidavit and take that to SARS for the 2012 year.