Replacing broken levers

I just snapped the left shift lever (chainrings) the other day. I have Campy mirage shift/brake levers with a Veloce crankset. I believe they are 2001-2. What all will need to be replaced? Since the parts are a few years old, will I need to replace both shift/brake levers or will the LBS be able to get a matching left lever? Or, can I get a newer left lever to work with the older right lever? I just want to have some idea so I don't get ripped off by the store for new parts I don't need.