WebService Testing - Tool or Means to create dynamic response based on request

I'm looking test few complex web services. Looking for a tool where I can paste the request XML and it will spit out/display the response XML.

Not looking at server-based solutions as the application is behind a corporate firewall and it's a pain trying to install an application or provide internet access to the application being tested.

The response has 2 elements - some ids/ref from the request that needs to be present and second is some new values.

Thank You