That's odd. I haven't bought one in a while, but long ago when I did buy them it always had the rod. Have you tried online parts distributors? Just do a Google search on "VW Rabbit fuel distributor".
I did a search a couple of days ago and found several sources for the distributor without the plunger. One parts distributor indicated he had the part but I can't call him until Monday. Maybe . . . Don't by any chance remember who you bought from before?