Also, the finder uses 1024 byte "Kilobytes" while I am pretty sure
that du is 1000 byte Kilobytes.
It is not.
From the man page of du:
"If the -k flag is specified, the number of 1024-byte blocks used by
the file is displayed,
otherwise getbsize(3) is used to determine the preferred block size.
Partial numbers of blocks are rounded up."