If you have already had a significant change in your voice, I am not sure that Model Talker is a viable solution as the Model Talker voice will be a replicant of your current voice. I went through the process with fingers crossed, but my voice had changed so much before I started, the voice created sounds nothing like my voice prior to onset.
If you do go with Model Talker and you have a Windows-based device, the Narrator function built into Windows 10 will allow you to use the MT voice as well as several other voice options. The narrator is a little clunky right now, well a lot clunky, but it will read back whatever you type in Word or Note or Notepad. The good news is they are working to improve it with each release.
Dave