I wouldn't jump down your mortgage broker's throat. Most banks don't require the SS card unless the file is audited for compliance. You can stop by a social security office in your area. They won't be able to give you a new card but they will issue a letter stating that this SS# belongs to you and that a new card is being issued. This should satisfy this condition. I've run into this problem before and the bank will take this letter which you can get today.