The best place where you can get a legal image is at a repair shop as part of a repair or upgrade. Search the web for a service shop close to you.
You can also buy the SSD from a DT Research dealer as an "upgrade" with the OS already installed. I can't find a part number but they use to sell the 4GB internal flash with XPte pre-installed. Just plug and play.
Also, with your unit serial number and UUID you could get a replacement CD of the original OS the unit shipped with - get that direct from DT Research support.http://dtresearch.com/support/support_contact.htm
However, if a third-party integrator changed the original OS then that would be useless.
If a "legal" image is not desired, there are a lot of places to download Miro XP or other hacked images of XP that you could install. There are a lot of posts in the forum with links including drivers. These tablets also run Linux or Android X86 - again, search this forum for tons of info.
Best of luck, -Dave