NORTON Ghost 15 is not genuine Ghost, but a consumer-only (as indicated by the "Norton" brand, which is only used to market consumer tools) backup tool which is a subset of the Symantec Backup Exec System Recovery product. This alternative product replaced the content of the consumer "Norton Ghost" product in all the editions of "Norton Ghost" after Norton Ghost 2003.
Current Symantec products which include the genuine Ghost tools are
Symantec Ghost Solution Suite and the Altiris Deployment Solution products; these include 32-bit and 64-bit Windows, 32-bit Linux, and DOS executables for Ghost (amongst many other tools and capabilities). The page for Ghost Solution Suite linked shows the prices for the main license bands of Ghost through the Symantec online store, although there are of course volume and educational license programs which can modify this pricing, as well as special VAR contracts available for computer manufacturers; those alternative arrangements require you to work with a Symantec sales representative.