You may well have someone within your network who would make a good Sales Director but would they make a GREAT Sales Director.
It is important not to hire in your own image and look for the skills and behaviours that are complimentary to those already in the business.
A top-performing Sales Director will drive up sales and greatly increase your profits.
Great sales people are always in demand and there are only a few of them. Even when times are tough, companies will not let go of their best performing sales people. They let go of the those who do OK. In order to succeed you have to be able to lure away the top talent from your competition.