Help! introduction of armbands episode ?

I need help tracking down which episode my mum was in she was asked to swim using the new armbands which had been brought out for non swimmer's. She was a teenager at the time and she's going to be 70 this year and she never saw the episode herself and I thought it would be nice if I could get some on for or if anyone would be able to point me in the right direction to get a copy of the show or some photos from it.I think it must of been between 1958-1961 as my mum would of been 13-16 years old and living in Oxford at the time it was filmed. I would be most grateful if anyone could help
,thank you
Kate