Hi Nic,
I've found a few more examples since I posted this. One on ebay which has a lot of points in common - the concave base and partial pontil, plus inclusions in the glass : 160101858940.
Also found a divine Italian piece (220079302874), and most suprised by this one which has a Whitefriars 9090 attribution (270105603992).
I wouldn't think this is interesting enough, or of sufficient quality, to be Michael Bang or Jesper Sødring, but it might help other GMBers searching for "folded rim" in the future.
Happy Easter
Cat