Srsly? I think a very dark brown watch strap, like very dark, not a chocolatey color, would be quite unoffensive with a fit that had black shoes and belt. Ive done it and I am not even embarrassed to say so!
But no, I would never wear a dark brown belt with black shoes, though I think its not quite the same with a watch.
Ymmv I guess.
Money? No idea. The Euro wires I have done were to other countries and they took 48 hours max iirc.