The best scope for anyone to have is one you will accually use regularly and you will also enjoy the views from it, an 8 inch dobsonian is a good choice or perhaps a 127mm or larger goto mak or sct, but this could break the budget of $300 by a considerable amount.
If the scope must be of refracter design and a budget of around $300, if you could stretch to $350, These zoom Binoculars may give better views than a cheap 60mm to 80mm refracter with several eyepieces, being of zoom design and 80mm objective for each eye several magnifications will be available it should give great views of nebula, star clusters, planets and the moon and even if she decides to get a larger scope in the future the 80mm zoom binoculars will still be of great use.
The binoculars can be made more stable for viewing elevated objects or higher zoom magnification by being mounted on a tripod (homemade or modified), or by being rested on the side of a large stepladder, or just lay back on the ground on a comfortable bean bag.
I am now tempted to buy these for myself......!
SAXON SCOUTER 25-125X80 ZOOM BINOCULARS at $349.00
http://www.sirius-optics.com.au/bino...inoculars.html