Easiest way is to order a Barnett cable. All they'll need to know is the bike and the handlebar height. Lancer on this forum can get them. He's a dealer for Barnett (among others).
Or go by your local custom shop and see if they make cables.
These are 15" rise, right in the height range you specified.
Clutch cable is a 4 inch or 6 inch longer than stock Kawasaki VN800A unit from Motion Pro, $26 USD. Throttle cable is a Honda version from Motion Pro, you can do the same thing with a PULL (Vulcans are a dual throttle cable) cable 4-6 inches longer than stock. Any catalog that lists Motion Pro cables will have the over length ones.
Cheap.