There are many Hawaiian islands and every island is different, this is for Oahu only:
We don't rent foil gear due to insurance/ liability issues. I believe Hawaiian Watersports in Kailua offers some rentals but I would say it may be best to bring your own gear that you are used to. I highly recommend taking a lesson with an experienced foiler that can show you the good spots, point out hazards, and will greatly accelerate your progression, whatever level you are at. We don't offer lessons, but these are our recommendations for learning to foil on Oahu.
www.blueplanetsurf.com/blogs/news/learn-to-sup-foil-in-hawaii/