STL file for 3D printing

We like to hire experts for creating 3d printable STL files. In this project, we are looking for a specific model to print. We can only provide a non-manifold stl file, which acutually shows details and sizes perfect. Anyway, this file is not printable. It may could be used as a blue print to make a printable file or repaired (which we think takes more effort than make a new from zero). Furthermore it needs to be split in parts, to have easier handling for later processing.