Small PLA Prototype 3D Design

I need a compact prototype model—no larger than 10 cm in any direction—designed so I can drop it straight into my PLA print queue. The focus is on accuracy and print-ready geometry: clean manifolds, proper wall thickness for typical 0.4 mm nozzles, and orientation that minimizes supports... (Budget: $10 - $30 USD, Jobs: 3D CAD, 3D Design, 3D Modelling, 3D Printing, 3D Rendering, AutoCAD, CAD/CAM, Solidworks)