Yeah, I just got that one off of someone's friend safari. I swear, I believe that the odds of finding a shiny in that place are lower than anywhere else...
As for that Archeops, I got this off of a wonder trade for some strange reason. I also didn't know that it was a shiny until I looked at its summary.
Lastly, I got that Shaymin from a wi-fi mission from Guardian Signs. It's the same deal with the Heatran & Manaphy.