The prints were found on eBay as Queen Victoria Court Beaut(ies). The National Portrait Gallery in London may have a version of this Lady Fitzalan-Howard portrait dated to 1849 that is not posted to the Internet. They do not have the Laura Paget portrait.
This Lady Fitzalan-Howard may be Augusta Mary Mina Catherine Lyons who married Henry Charles Howard, 13th Duke of Norfolk. Laura Paget's article in thepeerage is here. She held the title Baroness Templemore.