Corellian Corvettes were present at the Battle of Endor and used afterward (as was the Tantive IV - or at least I thought before I checked Wookieepedia) so this is quite possible. Also remember that construction of the Death Star was relocated several times, so debris may have left behind on several systems prior to the events of Star Wars. The Neo-Clone Wars has already assigned new missions to the Tantive IV, so it would be safe to assume that the ship may have come across a small, random piece of Death Star in one of the numerous systems in which it had been under construction.
The 10198 set is really too fat and stubby to look like the studio model; I never really liked it too much. The same goes for the 7665 Republic Cruiser - a Consular should have more of a "stretched-out look".