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The Minuet was basically a replacement for the Argosy 20 that went into production near the beginning of the Argosy line in 1972/73. The Argosy 20 and Minuet are very similar trailers, and sellers don't always know the differences between the two coaches. The Argosy 20 was basically produced through the 1976 model year into the 1977 model year - - with the Minuet 6.0 Metre being introduced sometime in 1977. Both coaches share the same length and similar weights; but the big difference is in the width - - the Argosy 20 has a floor width (exterior) of 7' 8" while the Minuet series has a floor width (exterior) of 7' 0". It appears that the final year for the Minuet series was 1979, but I haven't found any definitive confirmation of this presumption.
The Minuets have experienced a significant increase in popularity during the past two years. For some reason, the Minuets seem to be somewhat more common in the Midwest and West. I first became intrigued by the Minuets about four years ago - - prior to five years ago I had never heard of the Model. Then about 18-months ago when I acquired the '79 Argosy sales brochure, it was somewhat of a shock to learn that there are three Minuets - - 6.0 Metre (20'), 6.7 Metre (22') and 7.3 Metre (24') - - the two smaller coaches have single axles while the larger coach has the tandem axle. You can see scans of the Minuet floorplans by clicking on the "photos" button at the bottom of my post.
My suggestion, would be to check the Vintage Airstream Club classifieds frequently. My Minuet found me through the classifieds - - I was checking the ads just seconds after the ad was posted and was inspecting the coach less than 36 hours later - - it followed me home about 72 hours later. You can find the VAC classifieds at:
Vintage Airstream Club Classifieds
Another good source, at least in the Midwest, is the "Penny Shopper" classified advertisement papers that are often offered free in the lobbies of restaurants and grocery stores.
There have also been a number of Minuets offered on E-Bay, but most have been located in the Midwest or West. I know when I was shopping for mine, I even considered traveling as far as New Mexico to look at a coach.
Good luck in your search for a Minuet!