Imperial debacles, heroic last stands, the valiant defence of an island, arduous desert crossings and a deadly hunt with the PCs as prey, not predator can all be found in The Variscan War, a mini-campaign (25-40hrs) for medium-high level characters.
What to export or import....
Fabric: wool, linnen, silk...
Wood: raw-material, furniture
Metals: iron, gold, silver, copper...
Wine, beer, mead, spirits...
Animals: horses, sheep, swine, cows...
Coloring-powder (for fabric, ink...)
Raw-material to make fabric: unprocessed wool, linnen, silk...
Glass: Windows, figurines, glasses, raw-material...
Tea (not sure about my spelling here, but I mean the hot drink Englishmen drink instead of coffee!)