I myself have restored #4 and #5, very easy to do. Grab one or two to play with, the knots from TGN are reasonably priced and it's the best way to get an excellent brush on a reasonable budget...
I purchased brushes 4 and 5. Brush 5 also happens to be an Ever Ready too. I did not realize this at first. I will begin the restoration progress soon. Any recommendations on knots? I have a synthetic brush currently and I want to eventually have a boar and badger brush. I realize badger comes in many "grades" and I don't know which to choose. Can you really tell the difference in them?