I was wondering if anyone has attempted this before. I have looked online and found surprisingly little. We wanted to make a phone prop that would be attached to an Arduino and WAV board. It’s a push-button phone, and it seems to have 8 leads for the keypad, which is a 3x4. The receiver has 4 leads, 2 for mic and 2 for voice. I believe there is a magneto assembly which “rings” the phone when it receives a call. Thinking maybe to attach a battery to operate everything, and program various numbers which would then play a message through the receiver. Was also thinking of adding a remote button, that when pressed it would make the phone ring to play a specific message(s) as well. Anyone have any experience on the wiring side of doing such a thing?
It seems interesting but why to go through all this trouble when you can easily buy a keypad and gsm etc to design your own phone. 
Because I want it to look like a vintage phone on the desk.
I don’t think anyone has worked on it before, but if its like you really want to do it then I think you should do it. Play with it a little, like check the keypads wiring etc. I hope you succeed. 
Sparkfun made the [ Port-O-Rotary a few years back that should get you started. Granted, it was a rotary phone and not a push-button one but if you need it to ring, there is a circuit for that.](https://www.sparkfun.com/tutorials/51)