Caterpillar parts for 3600 series UNused

Good day I was wondering if you would have any Caterpillar 3600 series core engines?

3606 - 3608 - 3612 - 3616 

I am looking for the supply of a crankshaft for CAT 3616 engine P/N  7C-7976 or 361-8851.  Both used and new are accpetable, but preferred used crank with standard size.

Awaiting for your soonest reply!