Depending on what the dealer has to say you've got a few options. One being a new one from the dealer, a used one from ebay or craigslist, an aftermarket or sending it to a place like united radio that repairs radios. They may or may not be able to repair it (depending on the availablity of the parts) but I would go aftermarket. The new nav unit will be up to date and you can get parts to make the OEM steering wheel controls work and possbily some extras that weren't available from the factory.