I'm looking for the same for a D8 2U
Gary, I got all my water pump rebuild parts from the local cat Dealer. My serial number is 11867. I posted a few pictures and parts info a couple of years ago. Should be able to do a search and locate. I did a complete rebuild. Just as well do it all as along as you have it apart. Need a small puller or build one. Not a difficult project at all. Getting it off is the most work.
Cat don't seem to keep the rebuild kits for too long but the individual parts are usually still available.