I remember talk of a speedo repair kit for old chev trucks that could be used to fix our speedo cables. From what I remember it's a peice of cable that you would cut to length and then crimp on the correct end to match the original. then slide the assembly back into the original sleeve. I think this was the cheaper fix?
Also in the tech vault I think there is a listing for an old Honda cable that fits our bikes and has an elbow to relieve the stress where the oem cable breaks.
Hope this helps. NR