Perfect STL File Restoration for 3D Printing

I have an STL file with missing surfaces. Unfortunately, I don't know the software used to originally create it, but I'm seeking an expert who can assess and repair the file for 3D Printing purposes. You are welcome to ask for a copy of the STL file. Even zipped, it is too big to attach to this message. Your task will include: - Assessing the condition of the current file - Repairing the missing surfaces - Recommending the best 3D printing technology for the end product I'd prefer someone fluent in AutoCAD, SolidWorks, or Blender, but open to other platforms if that suits my project better. 3D modeling or animation skills, experience in 3D printing technology or virtual reality, and mastery of CAD are all great attributes I am looking for in the successful candidate. Your ability to determine the best course of action in restoring this STL file is crucial. Please apply if you think you have the necessary skills and experience. My goal is to 3D print the part, probably using PLA filament, for investment casting.