Hugger,
Cable length will depend on the rise and width of bars as well as how high the risers are. There are other variables as well. It would be virtually impossible for a company to list every possible combo with the appropriate cable length.
Generally, a tape measure is your friend. Remember, your wiring may need to be lengthened also.
What year and model of bike do you have now??
Suggest you bring your machine to a good indy or dealer and they can help you with all your concerns.
Acky