If you are looking for official documentation, the Stemme USA Downloads Page is the primary resource for both FAA and EASA manuals.
An OCR-processed manual that allows you to quickly find V-speeds or emergency checklists during pre-flight planning.
Facebook Groups like “Stemme Owners & Pilots” or dedicated forums on often have a “Files” section. Because the S6RT is a niche community, members frequently share scanned copies of their AFM supplements. Ask for the “Revision 7 or newer” PDF. These are often scanned on professional office printers, yielding extra quality results.