Frank Zappa and the Mothers

From farbror-sid.se

The original uploader Farbror Sid is not sure what Zappa album this poster, by Dave McMacken, came with. Anybody? I've been looking around on the web for a while and I can't find this poster or any references to it. Maybe it's very rare in real life too. I seems it's a Mothers (of Invention?) jubilee and I'm counting six candles. Frankie himself says "established in 1964" and in 1969 he disbanded the original Mothers of Invention and formed the Mothers...
Anybody?