watchu5

I know there are plenty of rep cases available for the sub/gmt/etc style but I cant seem to find as much for DJ lower priced ones are available easily through raffles but ive emailed the seller and he warned me theyre not water resistant enough for the occasional swim which may happen since there doesn't seem to be much available between raffles and gen (gen which I can't afford) is there some way to improve the water resistance of the raffles cases ?