I've heard
Mara pronounced mostly as MAR-ah (or MAHR-ah), but occasionally as MARE-ah, rhyming with
Sarah.
Maura, which I've only heard a few times (and on actresses at that), has been said as MORE-ah, rhyming with
Laura. So the sounds are very different to me. BUT, I can definitely see pronouncing
Maura as MAHR-ah. Phonetically it makes sense. *shrugs*
~
Heather~