To answer your first question - yes Land Pride makes very good equipment.
The 48" will work fine - IF you dont ask too much from it. If you are leveling simple dirt/gravel it will be fine, if you try to bite too much - it will be too much for your machine - specially with only 2WD.
what do you plan to do with a box blade? Do you have ag/r4/turf tires? Do you have ballast on the front?
I have 160 lbs on the front,m&s truck tires on the rear ,loaded,with chains(for the winter)
Main use is maintenance of 130' gravel drive way, smoothing of trails through back of property