I think that if anyone wanted to obtain a supply of these tubes, Pechiney, the very large French aluminium processor would probably be able to supply.It was this company that provided all the tubes to companies such as Vitus over the decades.
I think that the tubing ocmpany is based in Annecy..a very attractive town on its own lake, and reputed, after a poll had been taken by a magazine, to be the town in which the largest number of French folk would prefer to live.
twixt vineyards and the Alps it makes a great place to be when the Tour is nearby.
Norris Lockley
Settle UK