source-less packaging?

[Jack Howarth]

    Is it possible to suppress the need for a source file a Portfile?
The fink packaging uses...

http://patch-tracker.debian.org/patch/debianonly/dl/xorg-server/2:%v-10.lenny4/debian-dir%%20only%%20changes

as the Source file. Unfortunately the debian patch tracker server has
been down for years and fink has just been using copies cached on
their mirrors.
     Since I have a copy of this file from their mirrors, I was hoping
that I could craft a Portfile with no source but only a set of patches
in the files directory. Is this possible? If not, what is the
recommended solution when the original source url is dead upstream?
                  Jack