[Shalimar]

Is the starter missing or is it non-functioning? If it doesn't work then I would send it out for overhaul. If it is missing then I would look at Sky-Tec light weight starters. I had one on my 65 337 rear engine and it worked well. I believe that the model number that you want is a C24ST5, Aircraft Spruce has them for $567.00. A couple of other thoughts: Sacramento Sky Ranch has some interesting comments on the light weight starter. Apparently they don't work well for repetitive starts (20 or more per day). Also, with a light weight starter you cannot rotate the prop backwards. I would recommend staying away from Kelly Aerospace starters (or any Kelly product for that matter) Perhaps others on this site can comment otherwise, but my experience with Kelly stuff has not been great.
Good Luck and get this back in the air!