Your Caravelle looks like an easy refurbish from the surface. It has the same basic floorplan as the 6.7 Metre Minuet that was discontinued with Argosy production at the end of the 1979 model year. I suspect that if you measure the width of the floor, you will find the coach to be very close to 7' wide -- if Airstream was actually using the Minuet as the model -- the tandem axle would not be found on the 6.7 Metre Minuet, however.
One thing is certain, you won't find a sibling to your coach at every Rally as it seems the Caravelle was only offered in 1980.
Good luck with your project!
P.S.: I wouldn't be surprised if most everything in the interior is original except for possibly the lounge upholstery. I am almost certain that the carpet is original as that exact carpet was OEM on my '78 Minuet.
Kevin D. Allen
WBCCI (Lifetime Member)/VAC/Free Wheelers #6359
1964 Overlander International/1999 GMC K2500 Suburban (7400 VORTEC/4.11 Differentials)
1978 Argosy Minuet 6.0 Metre/1975 Cadillac Eldorado Convertible (8.2 Liter V8/2.70 Final Drive)