TCP is definitely a limiting factor. Honestly you can write your own scripts to do this probably easier than finding a tool. Calling SOAP endpoints repeatedly would be pretty straightforward to do in a simple C# console app or unit test project that would also allow you to log and handle specific tests. You could probably use Powershell as well but SOAP is a little messy.
As for public tools the only one I could find is SOATest. The standard tools like SoapUI only work with HTTP I believe.