Its not just a screw that threads into the other part? VTR234002?
Reason i ask is i cant see any obvious ways on the PDF to keep that said pin from falling out, which makes me think its a threaded screw?
Usually you only get shafts, but its normally just a picture of shafts on their own, JE's picture is very misleading and worth messaging them about.
The white parts are Pistons