Well - here I go tooting the Chris Pye horn again. He has a FANTASTIC chart in his first Volume book on Tools. Showing a pretty full range of sweeps and sizes in mm's and inches from 1/16 (2mm) up to 1 1/2" (38mm). This is the Sheffield list of numberings and sweeps. Which you can compare to the Pfeil (Swiss Made) set linked above.
He suggests comparing whatever set you have to his chart, marking the ones you have and carrying the chart with you when you visit flea markets, store etc. so you can do an on the spot comparison to see of a good deal fits in with your needs.
Me - I am off to a huge flea market here in southern NH in the AM. Here's hoping I make some interesting finds. ;-)

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ChuckT