I would ask the Garage to approach the main distributor on your behalf, or write to them yourself, setting out the situation. Just outside warranty, I would expect 50% gesture, but that totally depends on the brand, some will be better CS skills than others. What would also stand to you is if you have have a history driving the same brand.
I would put something in writing, always gets a better response.
I don't think there is any recourse with your statutory rights, unless you have had a history with the same complaint?