First of all, congratulations on your "new" Airstream! You've come to the right place to find out all you ever wanted to know (and more) about pulling a trailer ...
The items you're describing sound like they belong to a weight-distributing hitch. Likewise, the person who sold you the trailer was describing such a hitch, coupled with an anti-sway device that will help control any sudden side-to-side movements your trailer might make while towing. When used together, these two items vastly increase the safety and stability of your rig.
Now for the fun part: there are literally dozens of combos to choose from, if not hundreds. You can learn a lot by browsing through the "Towing, Tow Vehicles and Hitches" forum, which you've already found.
I went from knowing exactly ZERO on this topic to a pretty fair level of knowledge rather quickly, thanks entirely to this forum.
I also have a '65 Airstream, and I use an Equal-I-Zer brand hitch, which combines the elements of weight distribution and sway control into one unit. It's a popular choice on this board, as is the Reese Dual-cam hitch. Google either one to find their web sites, and keep browsing these threads ... I guarantee you'll find what you're looking for.