The answer as to whether the weight distribution bars will be necessary is dependent upon your tow vehicle. With my '78 Minuet which has a loaded weight that is likely very close to the loaded weight on your Caravel
, I always use the weight distribution bars - - this is in part due to the fact that I am a big fan of the Reese Dual Cam equipped Straight Line Hitch.
You will likely find that the weight distribution bars from your Argosy 29 are much too heavy for a Caravel. I have three sets of weight distributing bars - - 500 pound for the Argosy Minuet and either of my primary tow vehicles, 750 pound for the Airstream Overlander/GMC K2500 Suburban, and 800 pound for the Airstream Overlander/Cadillac Eldorado Convertible combination. I have found these combinations to be necessary to get the best performance from my Dual Cam Sway Control system, and know that Reese's technician at the 1998 WBCCI International Rally in Boise, Idaho recommended that the weight rating of the the weight distributing bars be nearly equal to the tongue weight of the trailer - - the Minuet has a tongue weight of 550 pounds when loaded for a long caravan, and the Airstream Overlander has a tongue weight of 775 pounds when loaded for a long caravan.
If your tow vehicle is a 3/4 ton truck based vehicle, you may be able to get by with a weight carrying hitch of appropriate weight rating. I would, however, suggest that some form of sway control would be desirable as I have noted a slightly greater tendency for my Minuet to be affected by passing semis than the Airstream. In either case, I have towed neither trailer more than 250 miles without a sway control (the first trip home with each trailer was sans sway control - - all others have been with the Reese Dual Cam Straight Line Hitch).
Good luck with your new to you Caravel!