Airymouse: I never heard of paduasoy until you mentioned it (or maybe I had forgotten it) and I was sure you had misspelled it, but Project Gutenberg has the text of "The Tailor of Gloucester" on file, and there it is, in the first sentence:

In the time of swords and periwigs and full-skirted coats with flowered lappets—when gentlemen wore ruffles, and gold-laced waistcoats of paduasoy and taffeta—there lived a tailor in Gloucester.

I suppose your spell-checker doesn't recognize it (neither does mine) because it's just too obscure a word.