Here are some images of MPC's 1/72 scale Lambda Class Shuttle. From Wikipedia "
Lambda-class shuttles first appear in Return of the Jedi and were later added to the Special Edition release of The Empire Strikes Back. Joe Johnston, Ralph McQuarrie, and Nilo Rodis-Jamero borrowed elements from the skyhopper designed for A New Hope when refining the shuttle's appearance. Earlier versions were boxy, boat-like, or had TIE fighter-like components. Industrial Light and Magic's modelmakers made two shooting models, although CGI versions were used for the craft's Special Edition appearance in The Empire Strikes Back. The Theta-class shuttle in Revenge of the Sith was designed to appear like a predecessor to the Lambda class. A Lambda-class shuttle makes a cameo appearance during the docking sequence of Inara Serra's shuttle in "Serenity", the pilot episode of Joss Whedon's Firefly.