Where do I get crystal chipped glassware repaired?

I have three items of crystal glasses (2 whisky tumblers, and one short stem wine glass), that are chipped on the rim. Unfortunately, I can't remember if they are lead crystal but they're heavy, and they aren't stamped so I don't know whether they are Doulton, Wedgwood or Edinburgh glass.

I live in Lincolnshire and want to know where locally, I could get them ground down to use again?

Alternatively, if someone knows of a reputable company on the internet that charges reasonable prices and carriage I would appreciate the details.

Thanks