I don't know anything about any of them being considered the best but every knot I have ever purchased for a restore, all badger, I purchased from The Golden Nib (TGN). No issues at all, shedding, wrong size, customer service, etc. https://thegoldennib.com
Glad to see you back here, Dapper-in-a-can-man! That is a beautiful brush handle to be sure. I second Zykris' suggestion of a horse hair knot. I got a Vie Long horsehair after reading that it had the backbone of boar with the softness of badger. That turned out to be pretty much true. At the very least, horse hair is worth trying out. That's knot funny?