You may like to try "The Darkroom" in Cheltenham. See http://www.the-darkroom.co.uk/index2.html

I have used them for some time for slide processing and found them prompt and excellent. I had a slide film processed and scanned to a high res CD (opens to 18 mb) and I thought it was quite good. I intend to try them with a negative film soon. I also found them very willing to discuss your requirements if you phone them.
John