Where can I find cam part #827009?

The cam part 827009 is no longer sold separately.   Instead Volvo Penta sells a complete
kit that includes cam (21951370).

I also included the other three kits that you might need to rebuild your pump.   Volvo Penta
has split the single overhaul kit into four sub kits (21951370, 21951418, 22222936 and
21951302).