Mr. Pescador,
Yes, mine is an Alcan, Luxfer bought them some time after those tanks were made. The difference between 6351 aluminum and "Luxfer special 6061" is minimal. From what I read, some cylinders, in the 1982 timeframe were made with a bogus alloy that had the lead. I'll keep going for computerized VIP. If after 33 years it is still like new inside, I'd be surprized if something changes.
As for our friend in RI with the 1987 cylinder, perhaps he should call around a find out the attitude toward these in his locale. I called around Orlando, and got the OK. Hydro, VIP and a fill cost $25 around here, and I ended up with a bargain. In another town, it could have been a white elephant.
Happy diving!