Pitts2112, I wish it was that easy man.. i have plenty of normal cushions lying around in the living room! However, my club prefers I use something made of fireproof material and something non spongy to support my back and legs for the reasons Genghis has mentioned very clearly in his post... and to be honest, the reasons make sense. I would rather be safe and protect my back.
Based on all the advice received and nothing being available at halfords which fits the bill, I have ordered dynafoam from proaviation so will cut out my own. They can deliver it very quickly which is a bonus.
Hopefully ill find a nice seamstress to make me a pretty cover for it
cheers for all the helpful posts.. now i know this "short" problem isnt so uncommon!
*problem solved!*