Been a few of these cotton Speedo suits on sale on eBay in the last few weeks. They're all from the UK, make in the UK, so they have to be from 2003 or earlier, as Speedo ended manufacturing in the UK in 2003.
I bought one, it doesn't have a fabric content label, but is definitely mostly cotton with some Spandex. Does not fit as gracefully as a Lycra or Polyester suit, puckered around the legs.
Definitely did some "shrink to fit" while I was in the pool. But still a bit awkward feeling at the back rear.
They took forever to dry. I was dripping water for at least 10 minutes as I stretched after my swim workout. Lycra or Polyester suit would be close to try by then.
This suit is not going to go into "rotation," it's just a curiosity.
Colors are pale when dry, but get bright when wet. I suspect they were aiming for a "Madras cotton" look. I could see it bled some color when I washed it in the sink afterwards. I got the red/yellow striped one.
The care label notes that sunlight and chlorinated water are bad for the suit.
The auctions:
http://www.ebay.com/itm/132067746045
http://www.ebay.com/itm/132067744675
http://www.ebay.com/itm/142248887265