Admittedly I don't know much about this piece, but I will tell you what I know.

I purchased it about Eight years ago on eBay and as it was in the vicinity,  I travelled to a nearby town to collect it. The chap who sold it to me was about Forty years old and he told me that he had grown up with it all his life as it had belonged to his parents before him.

That makes it Forty years old from 1977. It is made of Alabaster as I think. I have photographed it from all angles including underneath so you can see it's construction. 

He did say that he had more Tintin ephemera up in the attic that he had inherited from his parents. I asked why he was selling and he stated that now he himself had kids running around the house he didn't want it broken!  He wasn't particularly interested in Tintin and wasn't really interested in it, he just had fond memories of it being in the house as a child and didn't want it broken.

The bust is approximately 14 inches tall and 9 inches wide.

I think it's more important than that given the importance of collectibles to the Tintin brand.

It was, and still is boxed in a (hand fashioned) polystyrene mould within a cardboard box.

I will send it as is, and within a timber cased box for extra protection.

You are also able to see (and collect the piece) in person. Payment must be through Etsy though - no cash offers.