not so sure the colour is correct for first third C18 - but think there's a chance that the gadrooning on the lower portions of the bowl were a feature, in the main, prior to bell bowls - however, these things always seem to overlap, so never entirely sure. If this were period, say 1700 - 1730, my suggestion is that there should be a higher domed foot and probably a snapped pontil scar underneath.
It would remain anonymous anyway, I'm certain, it's just whether it's genuinely old or not, but would agree probably a modern copy.