H.W.
I'm in Oregon, so I can't give you a recommendation for practitioners; that said... our son was diagnosed with a convergence insufficiency and ocular motor dysfunction at around 5 years old. We did eye therapy for nearly a year-- about 4 days a week, 15 minutes a day or so... it started out pretty tough, he was discouraged with some of the exercises, but after a while, once the work became more familiar, we could see progress. The following April, the vision therapist stated that we'd done good work, the convergence insufficiency had been addressed and corrected. (The ocular motor dysfunction is not curable, lifelong, so we did biofeedback exercises for it so he could learn how to use his eyes correctly and so they don't tire as quickly.)
I strongly recommend finding a good vision therapist who offers concrete, age-appropriate exercises and activities to clients. Our practitioner was able to explain how/why each exercise worked and also offered some everyday activities to encourage (word searches, hidden picture puzzles, Legos were things suggested to us for our son) continued eye strengthening. We still see him once a year for a comprehensive eye exam and to make sure his eyes are working 'as a team' correctly. I'm so glad we found out about this sooner than later. Good luck!