RacquaWater Shoes Quick Dry Barefoot Water Aqua Sport Beach Pool Swim Surf Diving for Men Women

I am a uk size 11 but cannot see this size , should I risk going up or down a size ?

Does anyone know where i can buy spare insoles for these shoes? I have lost mine, whilst leaving them out to dry.

I'm looking for a shoe that will keep water out

Are this suitable for gym?