1967 Commemorative Cover

While mounting some covers this evening I came across this piece from 1967 I thought was kind of fun. I generally don't collect beyond 1960 but I remember this one catching my eye, and I though, why not!



This cover sports all 10 commemoratives Canada Post issued that year, plus a Special Delivery etiquette. It has a slogan cancel dated Ottawa December 18, 1967 as well as a different CDS on the rest of the stamps.
Also back canceled Cornwall December 19. But I'd swear the back cancel is dated 1957!
Either poorly inked or time travel is a real possibility.

The bottom looks like an incomplete 6 but the top stroke looks like that of a 5- huh?

Those were the days. The Post Office issued a reasonable of stamps commemorating significant events or persons, and the cost for the year's output of commemoratives was 48 cents. The post office wasn't in the First Day Cover business so today we can find many different FDC cachets.

Of course plate blocks were the thing to collect and a minimum of 10 stamps had to be purchased for each corner block (20 for the 3 cent stamp I recall).

It's a nice cover.