The cost of a new F class seat (excluding the BA/SQ/UA etc 'private cabins') is close on £50,000
each. Even used, removed, seats are going for high prices - I looked at buying some of the old BA seats which had been traded in to Rumbolds (based in Camberley, Surrey) for the new private cabins - they wanted several grand each for them. I don't have their number to hand, but you should be able to find their contact details online or in the phone book.
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Happiness is a warm L1011