There is a lad who goes to Rufforth on the first saturday of the month (SADDLECRAFT), he is based in Sth Shields but will collect from the autojumble and post stuff out.
His work is excellent, I've had two seats done, if you want I'll dig out his number and post it.
The one at Wyke is motorcycle seatworks www.motorcycleseatworks.co.uk if I remember right. He did a re-modded seat for me. The price and quality were both good.