These are the pics posted here..

TSR AD&D Adventurer Miniatures

For example the bottom pic is of the 5711 Half-Elves

Yes, they are authentic, and yes, they were released to retailers. I've got several of them myself culled from large lots. There are a couple of the ones you selected in this  
** expired/removed eBay auction **
in the boxed set, but many were released in boxes and blisters. Finding minis in blisters these days is getting more difficult. Like PC sheets, people like to use them, so they are becoming more scarce as time goes on.

I've been looking for these blisters too to see if they exist. Some of the blisters are definitely hard to find or may not have been actually created.
What I can tell you is that while some of the miniatures were "produced" in small quantities in 1984. Dave Sutherland had created some as he worked on them, which is how some of these miniatures cropped up. A number of the blister packs never were actually in full production or released. I think it was fall 1984 that was one of those tumultous times where a bunch of employees got axed along with the entire miniatures dept.