Mine were a friend who is a teacher and my Head Keeper.
You should be able to use anyone who is of reputable standing as a referee. Does this man hold an SGC?
As long as you know him well and vice versa you should be fine, unlike an SGC, there is no reference on the application as to who can be a referee. On an SGC form it asks for a Civil Servant, MP, Teacher etc, not so on an FAC form.
I think he should be fine, does he own a business?
Regards
SS