Resize STL for C-Clamp

I already have a complete STL model of a plastic C-clamp, but two areas must be brought in line with new, precise dimensions before I print: the clamping arms and the base structure. I will supply a drawing... (Budget: $30 - $250 USD, Jobs: 3D CAD, 3D Design, 3D Modelling, 3D Printing, 3D Rendering, CAD / SolidWorks, CAD/CAM, Solidworks)