Prepend prefix in tar
The GNU version of tar supports the --transform option (and its alias --xform), you could use it like this
tar --transform "s/^$MYPATH/$VERSION/" -cf archive.tar.bz2 "$MYPATH"
For example, given this directory tree
foo
└── foo.txt
the command
tar --transform "s/^foo/bar/" -cf foo.tar.bz2 foo
will produce an archive like
$ tar -tf foo.tar.bz2
bar/
bar/foo.txt
To tar the current directory and add a prefix, this worked for me:
tar --transform 's,^\.,$VERSION,' -cf foo.tar .