dealers outsource to local companies that do automotive upholstery. Go direct to the reapholster and you will save the dealer markup. Choose one that specializes in multiple types of leather and styles. this is something that you would want to do in person.
Not sure if you mean seat covers to cover your leather seats or cos you mention reapholster you have a damaged seat? If it's any help, when I had my Sorento delivered the rear seats were ripped/slashed.....crazy but true ! The "leather" bit of the seats is seperate from the actual seat bit, ie. they are covers. I was in the dealers and watched them change mine. They zip off and on. Not sure about front seats, though would imagine they're the same??