Have you tried Google Voice? You can pick a number and then use Google Voice as an intermediary to make the call. The receiver only sees the GVoice number (assuming you do it correctly).
Sign up at voice.google.com and then download the app. You can change the settings so it lets you choose whether you want to use your GVoice number or your real number when you make a call. Voila. It also works with texts.
I personally use GVoice to maintain a consistent number even if I switch carriers, because you can usually forward calls and texts to the GVoice number and vice versa. For instance, if someone calls my work cell phone in the daytime, it simultaneously rings my GMail (PC app), work cell phone, work landline, and my backup cell phone. Beautiful.