Allow spoofing of outbound caller ID after verifying ownership of spoofed number

It would be very helpful in making sales if I could make a new RingCentral system spoof the not-yet-ported or un-portable number of the customer after going through a process of proving that they own the number. Many people will not answer a call from an unfamiliar number, and this is a major sticking point for many of my clients who have otherwise good relationships with their clients.