Are you looking for one of the full body suits like they wore in the late 2000's? If so, you could try a triathlon wet suit, pretty much the same thing.
For something that's cut like a current suit, but of a non-FINA-legal material, there are the Blue Seventy Core shorts and many other similar options. Triathletes often use these to train in the pool. Gives them some lift like a wet suit, but without the heat retention issues that can be problematic in a warmer environment.
