The nail nick difference is most likely just a standard manufacturing variation.
Judging by the lack of wire scraper on the caplifter, I would estimate that these would have been made c. late 1972/early 1973. 1974 is when they switch away from clip point blades and drop "Victoria" from the tang stamp. The very last of these have 4 turn corkscrews, so these predate the last Victoria models by a little bit. But not too much, since the scraper on the caplifter lasts well past the disappearance of the +PAT on the can opener in 1972 (patent expires in 1971).