My charger for my MacBook Pro

My charger for my MacBook Pro has exposed wires. It is still woking, but I am afraid the exposed wires will cause a fire or may even shock me. I am no longer under warranty because I bought my MacBook Pro in 2011. What can I do? I looked at chargers for this computer and they are $80 and I can't afford that being a student without an income. Please help!