Hi ledbetter!
I know cat has alot of parts for the engines yet. so you can try there. they are now called Cleveland brothers, but still helpful. There is also a cats parts source list on the main page of the discussion part of the forum here. many helpful people here and willing to give advice. What part of Virginia are you from? i live in Pa, near the pan handle of west virginia. pretty close to route 79 south. if you need any parts give me a shout, i might have what you are looking for.
Their branch is in Clarksburg W. Va.so if you call (88😎 232-5948 you can get the Ph. number.
I am still have some use d4 parts.
I recently was able to get everything I need for my D8800 (D😎 engine rebuild through Florin Tractor in Ca. 916-383-0317