I, too, would have voted for black. Browns are so diverse, that if you can't find exactly the right piece, it'll look off. Since the buttcap and rings are black, the black will pop the burl, instead of subduing it. JMHO.
With the white joint and white in those rings I'd love to see it with a white based linen wrap, white/brown would be awesome. I don't care for leather wraps myself but they seem to be popular with a lot of people so I'm sure it'd be a selling point, but also an added expense.