Easier than you think. Stainless brake and shifter cables are readily available. You can get them at any bike shop and they aren't too expensive. You need real bike cables because they have a special head on one end. There's different ones so be sure that you get the right kind. It might require a special order because the generic cables that most bike shops keep on hand are galvanized rather than stainless.

When you get ready to install them goto parktool.com. They'll have easy step-by-stem directions.