[VoiceOps] Porting numbers from Centurytel

Does anyone know of a SIP provider that can port numbers from Centurylink ILec markets across the country? We run into this often where a customer has remote locations that are in Centurylink territory and we can't port their numbers back to our network. Most of these markets have small Centurylink footprints or they are somewhat rural. Richey