Hello,
This is right up my alley: I have years of experience with C#, PHP, and web services.
I've taken a glance at the supplied PHP class and will want some clarification on some of the methods and what kinds of information they return - you know, the overall purpose of the web service. I'll also need a token or sandbox environment to test against. This is because I'd prefer not to do a simple copy, but really make sure everything works correctly before delivery.
We'll want to discuss which version of the .NET framework you want to target, but that won't impact the cost or completion time. Either way we'll want to use standard components of the .NET library for the service calls and XML parsing to avoid needing a 3rd party library.
You'll of course receive the full, commented source code and a compiled DLL. We can also discuss some getting started demos of the implementation code (C# and VB.NET).
I can likely turn this around faster than 3 days, depending on my schedule.
Please let me know if you require further clarification or have any questions.
Thank you for your time,
Brian Steffens