You also have to decide if you would rely on the heter mechirah under which some of those grapes were harvested by Jews during shmittah. That is a huge shaila to ask your LOR. The question of how much you can pay for these wines, Otzar Beis Din as well, can come into play.
Thank you for bringing up this important issue. Kedushas shviis is part of the fruit/vegetable regardless of where you are.