That shipping charge is about average for ordering livestock off the internet. If you went to the post office, you'd find the charge to be about that, plus whatever is charged for boxing materials such as heating or cooling packs
Most sites have an order threshold that will give you free shipping, unfortunately you probably wouldnt be buying enough for a small tank to hit that threshold, but you could see if there are any local reefers that would want to go in with you on an order - that would make it easier to get the free shipping