Mercury program was the first human spaceflight program of the United States, running from 1958 through 1963. An early highlight of the Space Race, its goal was to put a man into Earth orbit and return him safely, ideally before the Soviet Union. There were 2 Redstone launches and 4 Atlas launches. The program took off from Launch Complex 5 and 14 at Cape Canaveral Air Force Station.
I recommend turning on "Advanced tweakables" in KSP settings.
To download Redstone/Atlas rocket go to the "Files" section.
Here are my other projects.
Redstone MRLV, Atlas LV-3B
Mercury capsule