STS-4 Space Shuttle. 282 parts. Capable of lifting 0-42 tons (full orange and full yellow tank with docking hardware) to 300km orbit. See cargo subassemblies in forum thread.
Please read forum thread for flight profile, and loading instructions. Very easy to load and fly, very capable. Download cargo subassemblies to load into its empty bay, and adjust your fuel accordingly. Balanced perfectly to fly up empty bay and fly up with 42 tons of payload, with only adjusting fuel amounts needed. One of the most beautiful NASA Space Shuttle replicas possible in stock KSP. Beauty, capability, and easy to load and fly… who would have thought such a craft possible?
STS Space Shuttle KSP Forum Thread & Subassemblies Catalog: http://forum.kerbalspaceprogram.com/threads/108219-STS-1-Space-Shuttle-%28NASA-Replica-Easy-to-Load-Fly%29-Full-O-Y-Tanks-to-Orbit-VIDEO-CRAFT.
The following subassemblies can be downloaded in the forum thread link above.
STS SpaceHab (STS-107 Columbia Memorial Payload)
STS Operations Module w/ MMUs
STS Fuel Pod (42 Tons of Fuel and Monoprop)