I don't want to sound pessimistic, but I don't thing this can be made through scripting or something similar.
In any case, you would need an (extra) external encoder to make the wav's,
... or you could offer your cash money, a piece of your soul and a good Spanish Rioja Vino Tinto to the MM developers and hope that they would be able to take some time "off" to program this.
OR, maybe MediaMonkey stores the ripped wav files somewhere before it converts them to the mp3 format (if MM doesn't encode on-the-fly). If you could capture these temporary wav's, you would be saved.