Sorry, for any confusion I was agreeing that Anthony's piece at the a the start of the thread being definitely by Harris.
I just got an email from Ron, who kindly responded to my query about the Chalice, which seems to echo Christine's thoughts.
To paraphrase Ron's email. Indeed the Chalice is a modification of Michaels earlier design as produced by Joseph Said, so the style and date match.
It would appear that Elizabeth has not owned a Said goblet and also would have been back in the UK from 72. The only other thought is that coincidentally, the piece was purchased at the studio and asked by the purchaser to be signed by the 'Betty' in the their life.
Finally, Elizabeth Harris, was only known as either Liz or Elizabeth and Betty would not appear to have any reference to her.
Hope this helps.