Further to Joe McKishen's REALLY helpful posting, do remember that you can order auto touch up paint from several eBay dealers. Cheap and easy.
Such as this:
http://shorl.com/
Just provide the make, year and colour. Easy!
And this stuff works. Like a perfect match to Raleigh 1950s Polychromatic Electric Blue (Lentons, Clubmans, RRA etc): current VW Bug Blue Lagoon. I'll wager most of these bicycle paints were auto enamels from the get-go. Except of course for Bianchi's old paint mixer. I bet he sold batches to Fiat, though.
Peter Kohler
Washington DC USA