All the way from England ! (U.K.)

Welcome to the site, Antony.
There were 173,638 Dusters made in total sold to the U.S. market, it does not include Canada or Export cars. (All engines)
Of those, there were 22,117 Duster 340s made. (total)
21,799 for the U.S.
3,401 3 speed standard
7,390 4 speed standard
11,008 automatics
Is yours an Export car? Which transmission does it have?
It's a very nice looking car indeed.
Great to have you aboard!