I don't believe there is a complete kit out there for all the panelling/chips/ detailing. It looks like the person who built this cut hundreds if not thousands of pieces and glued each on separately. You may be able to get certain pieces, such as guns perhaps, but these guns look like they have been modified much the same as the rest of the SD.
Search on this forum, in the classified section and on starshipmodeler.com. They usually have upgrade parts for several differ not kits there. Failing that, check Google/Bing.
TazMan2000