Back when I first put together my Death Guard (for use at AdeptiCon 2007), I was using the Space Marine Codex of the time. My Tactical squads each had a lascannon-toting Marine (seen in the back row above). I decided now was the time to pick up a few new lascannons and missile launchers (below) from Forgeworld to round out two Heavy Support squads.
Additionally, I took a few old plastic parts and new resin legs and backpacks to build three Death Guard Apothecaries. I've decided to go with Black Templar torsos, the tabards will be painted in a deep red. Should look pretty cool against the green of the shoulder pads.
Cheers
Dave