The Kerbal X is a stock rocket in KSP. It is used in the "Flight Basics" tutorial, and is capable of orbit and even the Mun.
Design[]
The Kerbal X consists of a core stage, with eight boosters. The boosters gradually fall away as they burn out. Once the core stage is out of fuel, the second stage takes over. This puts the ship in orbit, and from a low orbit can take the ship to the Mun.
The command module is capable of holding up to three kerbonauts. Once back on a sub-orbital trajectory, the capsule can survive a reentry, but the parachute can not be deployed until you are at about 800 meters per second, or else it will burn up. At sea level, the parachute slows the X down to about seven meters per second, which is easily survivable.
The Second stage, or "service module" has up to 800 units of charge, and landing legs if you are crazy enough to attempt a Mun landing. It also has a retractable ladder. This rocket has no scientific instruments, but it would work to add some instuments and a communications device.