Avondale and Mdina are not connected - but Mtarfa and Mdina are.
I don't know how we're going to know for sure - but loads of suggestions are a start, then some can be eliminated.
I don't think Wedgwood used lustres inside their paperweights - and their mushroom weights are of a completely different design. I have one (no pic to hand) it has a white stem and undercap, the cap covered in coloured splodges, all cased in clear - with a deep clear rim around the edge of the cap.
I don't know about Orrefors or Avondale.