please help ID this chair  

I know there is at least one ...
I know there is at least one in 'The Homewood', probably Paulanna or Robert will know, or you could contact the UK National Trust.
Got it, William Plunkett
http://www.nationaltrust.org.uk/homewood/

They are English by William...
They are English by William Plunkett in the 60s.
Pretty cool.

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You bested me.

Yes
He died fairly recently.
Here is his obituary from the Guardian
http://www.guardian.co.uk/artanddesign/2013/may/15/william-plunkett

wow that was a fast response,...
wow that was a fast response, thanks everybody.

That Obit
is very informative, not much to add -
Your chair is from the Epsom range. Most of his pieces are named after places in Surrey, England.
He trained at the same school as me (somewhat before me) in Kingston, Surrey, and didn't move far!

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Its Model WP1 if its 81cms high or WP3 if its 63cms high at the back. I have a bundle of original sales leaflets for this range which he gave me where they are described as 'The Plunkett Plan' - although they show a range obviously in full production and maybe it started out as Epsom. They were used extensively in branches of the (upmarket) shoe shop Russell & Bromley. He always blamed Thatcher for his business going under btw.

Kingston Range!
sorry, you're right! The Plunkett Plan was originally called the Kingston Range- the Epsom Range was the following series.

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