i work for a paint company & we make aproduct that has been used to refubish vintage car interiors. its called PVC94 & we could put it into aerosols for you. it will stretch & bend with the leather & should it start to wear, you can go over it.
http://www.hmgpaint.com/content/data...tds_hmg/83.pdf
pm me if you are interested, i am sure i can organise a couple of aerosols for you
Alan