Madame starring Sophia Loren original Movie Poster 1962

Poster was distributed for display only & to be returned after movie run was over.
It is big- 30" x 40" & very heavy thick paper. Almost has a painting quality to it but is not linen backed. 100% original.
The poster has copyright 1962 Embassy Pictures on it along with the distribution clause & I absolutely love it.
Also, note the stamped "MADAME" 63-27 along the 2 edges. Take your time looking between the stamps at the detail of the midsection of this piece.

I hadn't seen this in several years & I unrolled it the other day & did a little research.
I immediately saw on eBay that this particular version of this movie poster is worth several hundred dollars & none that I saw were posters of this size & that were for theaters only. Makes me think I have a little something more special than those- Plus, no fold marks. Always rolled.

If anyone has any information on why this particular poster version is worth so much more money than other versions I saw for the same movie.
I don't think it was too racy/sexy for the early 60's... but I can't think why this one is so much more valuable in collector's eyes.

Also, any info on what the blue MADAME 63-27 stamps might mean.. it would be nice to ad to the story.

Thanks for any info or comments.
Cheers!