I have recently done a project similar to this "Design of gear box". In this project I designed the gear box on SolidWorks. I performed hand calculations to determine the size of gear, shaft, key and bearing selection. I verified the design by FEA on SolidWorks. I can show you my previous work for quality. We can discuss further details in chat.
I am the right person for this job. I will get it done on time with quality.