Unless you can guarantee they were not sprayed with chemicals to stop them reproducing well, I would not use them. I buy new seed each year. In UK we have potato days where you can buy single seed potatoes for very little, allowing you to have several different varieties. If that is not available to you and the amount you can buy is more than you can use perhaps you could share with a friend. The reason for using fresh seed is to reduce the risk of infection. The dear potato which we all take for granted can be a fragile beastie. Good Luck with your project. Why not join GOY it is free. Only the managers know who you are. You can even contact fellow members privately without divulging your true ID if security worries you. There is a wealth of experience to draw on whatever your gardening preferences.