My Jeep hits 300,000 miles

My old 1998 Jeep Grand Cherokee Limited has just completed 300,000 miles and indicated by the photograph of the odometer taken at the critical moment. Although a number of items such as the air conditioner and water pump have been replaced, it is still relatively intact with little in the way of rust. My friends keep telling me to get a new one but that would require money and making a decision. We will hold off for now or until a rod goes through the engine wall.