Would it be possible to graft on the top of one of the large ones? I have seen a couple threads where it was done. One of my favorites is @ClothAnnie’s tree in this thread: Wild callery pear rootstocks - #119 by ClothAnnie.
I also saw a mention of someone who cut one down to purposely create suckers to graft on to the next year. His bark grafts didn’t work and that tree was huge. I don’t know if that’s even a good idea, but I kind of want to try it. I have a few VERY VERY large Callery pear at my house.