The old Cmax Energi was a great car. My contact at the EPA owned one and loved it. However, so few were made, trying to track one down is an idea hard to justify. Why not a Prius or Prius Prime, which Toyota made in massively higher volumes, has a large cottage industry supporting them outside of the dealer network, and which is not discontinued?
As a Ford hybrid owner (2011 MXZ), I second the Prius recommendation. Mine’s fine, but I’d rather have a Toyota hybrid, which will be my next car. While it may not apply to the C-Max, Ford put a time-based reduction in battery use (about 7 years, I think) that seriously reduced mpgs and performance. I had to reset the battery’s ‘birth date’ to trick the computer.