Hi Andy et al.
I am 99% certain that it is St Mandé or Grenelle. It was sold recently at one of my local auction houses as part of a mixed lot with other paperweights, (where I was outbid...) before it appeared on eBay. I thought both sale prices were 'quite strong', but as I (er hmm...) have two near identical pieces in my cabinet, I am not that unhappy.
What worried me about it was that it had several bruises, and the stave basket was very close to the surface (as usual in these pieces) - so good restoration may not be possible. It had rather dirty clear glass (striations and debris) - not unusual - and the glass was rather grey - fairly typical. It is mainly the glass quality that makes me think it is St M or Grenelle rather than Clichy. It is hard to distinguish these two factories, in part because the founder of Grenelle (Charles Bredgen) started his career at St Mandé. He then went to Finland, before returning to work at Clichy (just to complicate things further!).