Well there is the Icon of the Hodegetria, a portrait of Mary painted from life by St Luke. Then again the icon was first mentioned in the fifth century, so it's authenticity is a little doubtful. The same can be said of pretty much any relic, including items such as the Holy Prepuce which might yield DNA suitable for comparison testing with a body.
The simple answer is that if a tomb was found, and if a body was found within it, there would be no way of actually proving that it was Jesus, and no way of proving that it wasn't.
The simple answer is that if a tomb was found, and if a body was found within it, there would be no way of actually proving that it was Jesus, and no way of proving that it wasn't.