If your fileset consisted of a GHO file plus one or more GHS files then you have NO chance of recreating the GHS files from the GHO and I think that recovering anything from the GHO without the final GHS file is also unlikely.
Basically, if you are imaging a hard disk using a DOS boot, the maximum file size that can be created on a FATxx partition is 2Gb, so a larger image is stored as a series of files starting with a GHO and then further GHS files, each up to 2Gb in size, until the entire image has been created. Each of these 2Gb files hold a subset of the files in the image, and if I am not mistaken, the final GHS file stores the directory of all the files imaged and which of the GHO or GHS files they were compressed into. I am sure Nigel Bree will correct me if my understanding is incorrect.
Depending on where these files were stored, are you unable to recover them from a backup (if server based) or by using an undelete utility (if workstation based) and if the machine in question has not been used extensively since the files were deleted. As I'm sure you are aware, files are not actually deleted when you delete them, all that happens is that the area of disk where they are stored is marked as "available" and the file entries in the directory are removed. Hence if there has not been much disk activity since the deletion, it may be possible to effect a recovery of the files The more the machine is used, especially if there is not much free space on the hard disk, the higher the chances that the "free space" holding these deleted files will be overwritten by new data.