Hello
This can definitely be done.
I know this can be converted so you do not need the flash player plugin.
Therefore its just a matter of dropping the FX into the narration at the same point and bouncing the edited file to whichever format that will be required by your streaming site. You can use MP3, WAV, AIFF, MP4, FLAC.
If you have a link to the Audio book I can do a free demo showing you the finished sound.
Please see my profile, I have been in commercial audio production for 25+ years in the UK & Australia.
Thanks
Carl