Chelsea Girl never shut, it changed it's name to River Island.
I found this:
In 1948, Bernard Lewis started selling fruit and vegetables, and then knitting wool from a bombed-out site in the East End of London. Joined by his three brothers, the chain expands to nine stores under the title Lewis Separates.
By 1965 Lewis Separates had an impressive 70 store empire in the UK and it was decided that the brand needed a new identity. Lewis Separates was re-branded to Chelsea Girl, the name chosen because at the time the King's Road in Chelsea was the hub of fashion, music and popular culture. Chelsea Girl became the first UK fashion boutique chain.
In the late 1970s, two of the brothers left the business, leaving Bernard, David and their families in charge. They formed the Lewis Trust Group, for which David ran the other businesses covering hotels, property and investments, leaving Bernard to run the retail operation. This allowed the company to expand into menswear in 1982 with the launch of Concept Man stores, before they were merged with Chelsea Girl to become one retail brand under the name of River Island in 1988.
When I first came to the UK in the 60s, I bought my presents for family and friends when back home at Marks & Spencer's or Woolworth's. Later, we has a M&S's in Paris, I loved it, no so much for it's clothes but for the stationary, soap, makeup but then it closed, but there's still M&S's Food . We also have C&A here. What about "Past Times"? I bought a lot of things from a mail-order with that name, copies of Victorian, Elizabethan, William Morris or Charles Rennie McIntosh bags, scarves, jewels or other trinkets.