I have never ordered anything from merit but i would assume that when people ordered a hard drive they would send them a hard drive with the version that matches the key they have in their machine. When you take a blank hard drive and install for example, force software from a downloaded ISO, it formats and partitions the hard drive, then uses a custom version of an old linux backup software utility called partimage to restore the partitions. Inside the ISO is partimage image files that contain the data for each partition. After its done restoring the partitions, it installs a bootloader and when you reboot, the bootloader boots the OS and loads a custom version of X window system (X11). During the boot process it reads the data off the key to determine the correct version info (country, currency..ect..ect).
So to answer your questions, yes you would get a hard drive with everything already on it for the version you need. I dont undersand why you want a hard drive with just the empty partitions.
I could make you a patch for the ISO that would only format, partition, and install a bootloader, but i dont see why that would do any good.