
However, upon removing the relic from the scanner, I noticed a faint etching on its back. Just in case you can't decipher my weak photographic skills (and the etching was faint), it reads: "June 13/73 Ontario Place Forum".

I guess the original owner thoughtfully decided to commemorate the button-purchasing moment, which happened to be the night these guys recorded their live "Backstage Pass" LP. Which you can sample at their official site. I recommend the tune "In The Shadows". Not only that, but according to the site they're still at it, 30-plus years later!
As for where I picked up the pin, god knows...