possibly use a medical ice pack vest under your suit ?
as i suffer from MS, the heat kills me. [but i love the summer !] i use one of those vests often, and always at carlisle.
they are cheap, and so are additional ice packs.
look up cooling vests or medical cooling vests. lots of choices.
the only thing i don't know is how tight your suit fits. these things are not big, but figure the ice packs at about 1" thick or so.