I would be very surprised if a compatible cable is available, someone would have found it by now but never say never.
Coxy, We don't have 'good bike shops' here any more ( anyway, not where I live). If you can't quote the exact part number, they can't help you. Repair a cable ? they look at you daft
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Alan, There are suppliers on the net who have cable repair kits, could try one of those but BS cable are 'heavyweight', replacements tend to be thinner. Specialist suppliers like Wemoto, Venhill or JJ Cables will remanufacture cables to a pattern, at a price !