You can see NRA's requirements
here.
As an NRA Training Counselor, what I commonly see are people who have very limited handgun experience and can't get past the basic qualification. Learn to operate a semi auto, double action revolver, and single action revolver. Learn to do things the way your NRA Basic class taught you. Being an NRA instructor is 50% experience, and 50% adhering to the NRA curriculum.
As far as finding a class, there aren't that many Training Counselors on the island, so it's not surprising that the classes are far between. LIFE does offer a class periodically, but we give preference to candidates who have been active with HRA/LIFE already. As OldFart said, you just missed the last round, so it'll be a while before that boat sails again.
NRA does offer listings for upcoming classes, which you can search
here. Note that this is not a comprehensive list, it is only the people who opted to use NRA's site.