I love a good mystery too. And coincidentally, I'm missing a perfectly-centered Canada MNH "Bluenose". My address is in the Members details.
Freaky, but the stamp image UR on the page right now is the stamp just mentioned. Karma? Can lightening strike twice? Let's see how this mystery unfolds...
Sorry, I don't have a MNH Bluenose to send you, but here's an image of my used copy. I think — I'm not sure — that the one you saw is mine. 'Tis a glorious stamp!
This is too weird to believe. I got home tonight and opened yet another random envelope of stamps from THE HOARD to do more sorting and right there at the top ...
Comparatively not the best centring or cancel but at a cost of basically "zero" I'm not sure anyone would be upset having to mount this in their album...
I want some of that karma! For the record, your stamp is "better" than mine in one sense: the roller cancellation shows that it was probably used as it was intended, as postage for a parcel. CDS cancellations like the one on my copy are probably philatelic. The postmark is decent too — DEC 23, 1929; the stamp was issued January 28 of that year.
Several years ago I got a phone call from an elderly gentleman who wanted to donate a stamp collection, which had belonged to his father, to my stamp club, the British Columbia Philatelic Society. It turned out that his apartment was just four blocks from my apartment, so I walked over to his apartment to pick it up. Right away I could tell that it was no ordinary collection.
There were lots of mint Canadian stamps from the 1930s and 1940s, along with lots of short sets of British Commonwealth stamps. Among the Canadian stamps: a block of four MNH Bluenose stamps. I told the man that the stamps he was offering were very valuable, but he said it didn't matter. He didn't need money (his apartment would be selling in today's market for well over a million dollars, I'm sure), and knew that his father would want our club to benefit from the stamps, so I thanked him and took the stamps home with me.
The next day turned them over to our club auctioneer, who lives near me and is is more familiar with Canadian stamps than I am. Soon after I got home he called me and said words to the effect, "Guess what was in that bunch stamps you brought over! That block of Bluenoses has a "Man on the Mast" variety!"
It did indeed. Here's an image of the block:
A few weeks later the club sold the block in a local auction; as I recall, we got CAN $1,500 for it.
Finally got my Bluenose with the man on the mast variety! Now that I have enjoyed it for a week, it is available for purchase. Photos may be found here: https://photos.app.goo.gl/CDS9UwptmKAwgn1Z9