Photoshop Plugin or Automation - Proof of Concept

I am seeking a developer skilled in writing graphics plugins for Photoshop to create a quick proof of concept for a filter I am designing. The filter can be written as a filter or as a "File->Automate" routine. Ideally, the filter will be written in C#. Here is what the filter will do: 1. Open the current layer in the filter window. 2. Create a scaled-down version of the image at 320 pixels for the longest side. 3. Run Unsharp Mask on that image, using pre-set values. 4. Display the results of that unsharp mask inside this filter. 5. Use that value to create the unsharp mask on the full-sized image. 5. Return that data to Photoshop.