None of my cars that originally had AIR systems had any kind of sealing washers on them. It seems like they just allowed the surfaces to crush into each other for a seal.
I used copper gaskets for sealing brake line fittings. Most auto parts stores have an assorted bin on them available or at least a catalog listing them by size and part number so they can be ordered.
Eventually the tubes will seal themselves with rust and carbon...
I seriously hate AIR though. More places for exhaust leaks and the pumps seem to die every year or two. I remove it from all my cars, but I understand that your local laws may not allow that.
'72 Jeep Wagoneer Custom, 360 V8
I love how arguements end as soon as Ristow comments. Ristow is right...again.