If you are running a WCF component as a service then hopefully the developer of that service made the port information configurable. Take a look at the service's configuration file. If they didn't then you aren't going to be able to change it. Note that normally this is in the system.serviceModel
bindings section.
If you don't actually need the service to run then use either the services
app to select the service and stop it or use powershell's stop-service
command to stop the service. Both require that you have admin rights.
stop-service nameofmyservice
If you aren't sure of the service name then use get-service
to dump all the services and find the name of the service (it is the service name, not the display name).