Original poster?

I'm wondering if you guys can help me out? I'm thinking of selling this poster but until I have an idea of its originality I'm stuck.
I've had it 7 years and the bloke I bought it off said he'd had it for years
It was a good price so I took him at his word. It has no printed text on it like the larger one's have on the edge, this is A3 size I've tried a few close ups so you can see the print style. The back has some signs of ageing and is marked from where i think it may have been displayed(perhaps on a dealers wall) and it has that old paper smell. The paper has a"smooth" finish to it and feels old Thanks.

Thackers, from your images it looks to be original BUT without seeing it in the flesh its always hard to say.