The Percy Family
The interest here, with respect to the history of Belchamp Walter, is to Sir William Harris who is shown as a descendant of Edward III.
The Percy family are common in both the family trees shown here.
It would appear that both family trees show a dependancy. I suggest that this could be bought by someone who wanted to have this as an accolade for their family heritage. So far I have located two examples of The Plantagenet Roll of the Blood Royal: The Mortimer-Percy Volume. I have a suspicion that there are many more.
The Alan Freer family tree for the Raymond family seems to repeat that of the Marquis of Ruvigny and Raineval