Spraying Pear trees

I have a number of pear trees in my garden which last year showed signs of pear scab and a blackening of the leaves. I have looked in various places for a suitable spray but have been unable to locate one. I note Jeyes Fluid is recommended in some circumstances but only when trees are dormant. Is it too late to spray for this year? If not what should I use and where can I get it? (I have tried a number of garden centers but they only had insecticides).