According to the book King Mod by Steve Turner, Sandra Lane—later known as Sandra Blackstone—disappeared without a trace in 1966, soon after the closure of The Scene Club, presumably moving to America to start a new life. I know it's not much help, but it's a start. You can also see two pictures of Sandra in the book.
https://www.amazon.co.uk/King-Mod-Meaden-Making-Subculture/dp/191273351X/ref=mp_s_a_1_1?crid=9EIAUOAO2IJJ&dib=eyJ2IjoiMSJ9.pwsUApVwSkVb74ix8D6wLQ.MGGkpjX_egfbqayL1gYh6Yiyxw3PXNz2KH6hoLKGOvY&dib_tag=se&keywords=king+mod+peter+meaden&qid=1739642650&sprefix=king+mod%2Caps%2C120&sr=8-1