I know I am pushing even Chowhound's acceptable food sanity standards with this sardine thing, so I'm not about to go waltzing into a store asking for vintage sardines unless I know they have them.
Narrowing this down a bit, they would be French in origin probably. One brand is La Quiberonnaise. Another brand is Chancerelle. There are probably others.
Here's the link to the general board discussion:
Updated 1 year ago | 14
Updated 2 years ago | 1
Updated 2 years ago | 4
Updated 1 year ago | 5
Updated 9 months ago | 2