I built this item set for my latest map called Race to STaDOS. It contains several Portal related items such as:

• Cakes (2 sizes)
• Cubes (5 variants)
• Turrets (normal + construction version)
• Buttons (normal + CP trigger)
• Camera (3 pieces: support, support pan and the camera itself)
• Radio
• PC
• Aperture Logo (2 sizes)
• Portals (2 sizes + 3 variants)
• Pistons (walls)
• Doors (2 variants)
• Water replacement
• Bumper replacement (blue gel) (road + platform versions)
• GLaDOS (normal + finish trigger)
• Wall light
• Asbestos see through spheres (2 versions)

Bumper replacement and water replacement requires the Race to STaDOS mod and just sits on top, without collision.