This has been a long debated subject.
I don't know of any repros of this poster, at least not of this size. Repros of a smaller version can be found all over the place (here for instance:
http://www.allposters.fr/gallery.asp?aid=472811481&c=c&search=16495&lang=2&Referrer=http%3A%2F%2Fwww.google.fr%2Fsearch%3Fq%3Daffiche%2B%2522le%2Bcauchemar%2Bde%2Bdracula%2522%26hl%3Dfr%26rls%3DGGLG%2CGGLG%3A2006-44%2CGGLG&SAID=472811481&SAIDTime=2%2F27%2F2007+5%3A52%3A57+AM&maid=472811481&AffClickThroughID=934527359&TID1=320582&TID2=1.
This said, there has been talk of the poster being reprinted at the time of release (still unconfirmed, to my knowledge). Horror of Dracula was a hit, and they may have ran the machine again. Both versions, if there were two versions, were printed in 1958 by Marcel Landais, owner of Affiches et Publicité, maybe a few days apart. One of them supposedly had dots on each side of "Interdit aux moins de 16 ans". There was also a mistake in the name of the printer, which may have caused the new printing.
What makes it difficult at this point is that both posters have been reproduced in books, some of them really old. Foremost French collectors like Jean-Louis Capitaine and Daniel Bouteiller both say the restrike is bogus. I had my poster looked at by Stanislas Choko who identified it as 1st release. But people at Dominique Besson might disagree.
Either way, whether it's this version or the other, both are amazing (because they're the same) and both are extremely hard to find and quite expensive.
Thierry