If you have an HD box on your account you will get either a call and/or a letter for the swapout of both your dish and box. The installer will bring the box with him when he installs your dish. D* because of very short supply will not ship a box out nor will they let retailers give out the new boxes unless its part of a new customer package where the retailer will bring the box out with the installer.
Don't bother calling D* because it wont make the process faster and they can't place the order for you. Now once supply gets in normal ranges this could and most likely will change allowing you to call and order it and have it shipped.