If you don’t fancy doing it yourself, these folks are in Leicester and not too far from you. Did a great job for me on our old 4/4.
http://www.auto-trim.co.ukWorth a phone call. At the time, my seats were 25 years old and needed all new webbing so I removed the seats and took them there in the tin-top. I would have thought they can do your seats without you removing the seats.
