One of the members ( see link for his sample shots:
https://www.flickr.com/photos/137833...4/23368905422/ ) uses a Olympus TG-4 ( for around $329) underwater cable camera is possibility with it)that is cheaper than a macro lens which starts at $5XX for a macro 60mm new, or around $3XX user, so that might be an option too.
msjboy