recently, I removed the steering column of my 67 big block car and noticed that the seal was missing. A closer look inside the column revealed that the seal must have been a foam type seal. I found a listing on eBay with a steering column seal that looked very close to the remains in my steering column. Part number C9AZ-3E629-A.
Finally I ended cutting a „doughnut“ out of a piece of black foam.
Laurent