I would be very interested to hear how you get on. We had a similar problem in our house, which we moved into in July. In our case the bricks on each side of the grate are loose. I serached a lot to get someone to fix them, but either people were not interested in what they said was too small a job, or they asked what seemed ridiculous prices. I think I was quoted about €300 to fix them, but can't remember precisely. In the end I bought those 'firesaver bricks' and propped them up at the sides. (Don't know what they are called - they make the grate smaller to save fuel). This is just intended as a temporary solution though - so if you find someone who will do a small fireplace job at a reasonable price please pass on the details!