Original would have been white hoods and cable housing too, so I think you can try whatever you like for bar tape. Unless it's plastic like the original, white isn't very practical anyway, what about trying a color that plays well with the copper paint?
Personally, I would have saved those Campy sidepulls for another project. Not only does the rear brake make an orphan of the brazed-on cable stop but the arms on Campy brakes are on the opposite side from the cable guides making for an unavoidable cludge with the routing. In my experience, Weinmann centerpulls with Kool Stop salmon repro pads brake quite well. If you decide to convert, I have the adjustor for the cable stop and will donate it to the cause.
It is a beautiful machine!