I might get shot down in flames here but as such you don't need a flying school as such to do the training. Any old instructor who is current on tail draggers can do the differences training and sign you off. The training also doesn't need to be done at a licensed strip although if you are going first solo I would suggest you do it with some sort of rescue crews nearby .
A post in the instructors forum might sort you out with a local instructor who if you already own your share in an aircraft can do it on your machine at your local airfield.
Atlantic in Coventry have a tail dragger training aircraft if you get stuck not sure if they rent it out as they use it to train the fuglies.
MJ
MJ