All the better, cos leather never really takes it as basically the dye sits atop the leather and always cracks where you bend your toes after a few goes.
Anyway, you can try Dylon Shoe & Accessories colour, which works well, but your choice of colours are limited. You can get them in Hickeys on Henry St., Dublin, but don't know where else.
For a better selection of colours you could try : Tulip® Soft Fabric Paint™ .
You can get it in Inspiring Ideas in the St. Stephen's Green shopping centre or there is an Art & Crafts shop on the 1st floor of the Jervis shopping centre that has them also. Don't use it from the tube when applying. Put it onto a saucer/ plate whatever and pick up only enough paint from that with a brush to apply to the shoe. Turns out quite well once you have the patience not to rush it around the soles, which you could mask so as you don't get the paint onto, until it dries.
Hope that helps.