Thank you to Gail and Doedo Schipper who have taken the time to digitize the CASA 1131 assmebly/parts manual.

buckerjungmannassemblymanual.pdf_page_7_of_51.jpg
Registered website users can click this link to download the book:

 http://www.bucker.info/index.php?option=com_docman&task=doc_download&gid=44&Itemid=67

It is quite a large download, but well worth it. While Bucker Prado SA were active in supplying Bucker parts, they would use this book as a guide. The page shown above is page 4/41 so a part would be identified by that page number and then the item number from the drawing. Still a good way to define a particular component.