Just a quick line to let you know that I found this locksmith, he's name is Aydin. I explained exactly what I needed and he came out the same day to check what parts he needed to do the job. He told me his cost and I agreed for him to carry out the work.
2 days later he arrived smack bang on time and spent 3 hours fitting the new locks and he did a first class job. Thanks very much for recommendation.