I've put together a complete Primo 2.4 US TTS Voice "package" for WinCE that contains the TTS engines, (7) different US TTS voices and some TTS-related UX "add-ons". Being that there are both Loquendo and Nuance voices here, you'll need a version of Primo that supports both (if you want access to all voices). I recommend Primo 2.4 (9.6.13.405512).
From the included README file:
iGo US English TTS Voices by JT - Version 2.0
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