The part number Frank listed, 75910131A, runs all the way thru 916, 996 and 998 RS catalogues. It's now obsolete. Can't get a part number on the pin in the Ducati Performance kit anymore as the kit is off the catalogue so can't do a breakdown. As far as I can tell you, it's going to have to come from elsewhere other than Ducati I'm afraid.
Mood: R U thinking what I'm thinking?......Oh dear!
Do you have a reasonable idea of the dimensions.
The clips have various names R clip, clevis pin clip,
If Ducati related sources draw a blank it might be worth a trip to your local farm machinery suppliers, they use pretty large clevis pin clips on..........er tractors and farm machinery.
Some motorsport suppliers have them in stock as well as similar clips are used as wheel nut retainers etc.
It's a reasonably generic part unless of course Ducati had some made to a particular spec/dimension.