Why prices are that high on Gibson's website I'll never know.
No, prices are not that much. Look at websites like guitarcenter.com and musiciansfriend.com. Those are the actual retail prices.
An R8 is a standard and the B7 is a custom. The R8 awill have the trapizoid inlays and no back binding. The top is maple and the B7 has a mahogany top. The finger board on the custom is ebony and the R8 fingerboard is rosewood. The B7 may be heavier as well.