Prototype 3D STL File Creation

I'm looking for an experienced 3D designer who can create a 3D STL file for a prototype I need for 3D printing. The dimensions don't need to be precise, but they should be approximately to scale.

Key Requirements:
- Expertise in 3D modelling software
- Experience in creating STL files for 3D printing
- Ability to design a prototype based on general scale and dimensions
- Understanding of 3D printing specifications and limitations

I look forward to seeing your proposals.