get one from the dealer... i believe might be the cheapest

Cummins

While you are in there, take the time to pull out each of the bolts that fastens the timing case to the engine block -- ONE AT A TIME -- add lock-tite and torque to factory specs.

I found all my bolts just barely finger tight when I did my KDP. My truck only has 55K miles... Fortunately my pin was still in place, though sticking out about 1/8".

Do the timing while you have the cover off. Much easier to see what's going on.