Fellow blogger Hugh Walter of Small Scale World recently acquired a set of Thunderbirds key-ring figures.
Hugh reckons they seem to be the same as those handled by Xandria-Holland of New York in the US . . .
(about 3/4's of the way down the page)
Another possibility is a Spanish origin maybe. I checked my Dennis Nicholson Gerry Anderson Memorabilia Guide and they look like these Dutch ones from 1968 too, but there's no makers' name.