If you own the 2007 model, they have a pre-drilled plate, right? If so, you will need to use Look (also branded Dynastar and Rossignol) bindings, because the plate is compatible with only that drill pattern. (I believe that it will also double your warranty.)
As far as which bindings to use, the Nova/NX/Axium series and PX/Axial2 series have different heels; the former is on the left and the latter on the right:
The PX heel is sold on the "performance" models; it is beefier and probably allows a little more elastic travel, on 12+ DIN models. The NX heel is typically sold in DINs up to 10 or 11, and all or most "women's" models use the NX heel.
Given her requirements, she'd probably be fine with either. And given the skier's specs, I'd be surprised if she sets her DIN higher than 7 or so. For reference, my wife is in the same range, and she has a pair of Novas on one pair of skis and NX11s on another.
As for lifters, if you already have a plate, they'd be duplicative. But if you get a better deal with lifters, IIRC, they're typically removable.
Nova and NX bindings are often available on eBay for less than $50.