content: We did not build ANY of it after the last mission. They don't keep spares of things at NASA. If they did this we would have 2 Hubble, 2 JWST, 4 spirit+opportunity, 2 Mars global surveyor... Seriously, the last "working" Saturn V engine was outside for ~50 years as an exibit for the space museum. They only took it up during the Obama presidency because they needed something to go off of to design the Orion SLS.