The recall involved the wrap around receivers that were not built with the re-enforcing plates on the inside of the trigger housing. The faulty stens can be ID'd from the washer spot welded around the change lever to give the area the proper thickness. Ill 301 in the book shows one of these.
The stens which had the re-enforcing plates spot welded in were not effected by the recall. A photo of one is shown on the top left of page 300 (illustration 299)..
From the dozen or so single wall wrap around stens that have passed over my workbench, the tubes seemed to buckle near the front of the trigger housing, where there was the least amount of metal. It would seem that many of them continued service in Canada right until the end.