How much does it cost to put a factory backup camera on a 2004 Honda Pilot with a navigation system?

Honda used to tell you on the website, but the new Pilots have standard backup camera's so they aren't an accessory anymore. I'm looking for an exact price. If not, an educated approximation would be great. Thanks.How much does it cost to put a factory backup camera on a 2004 Honda Pilot with a navigation system?It was not offered in that year sorry no software no camera