I've been dealing with some rust issues lately myself and I was talking to my local paint store. The gal that works there introduced me to a paint that is awesome. It's a bit pricey at about 13-14.00 a can but it works great. I bought it at the paint store which of course is cheaper than Amazon, but this link will give you an idea
https://www.amazon.com/General-Paint...910423&sr=8-18