I'm looking for a weight jacket to wear windsurfing.

I was hoping for about five to ten kilo's of additional weight. Not prepared to eat more or go to the gym.

Google has only shown examples that will send me to the bottom of the harbour. Safety is important.

I need a jacket filled with water, for 'neutral' buoyancy. A local brand, has a crash vest that looks grand, if only it were filled with water. Hint, hint, hint.......

Can the collective wisdom of Seabreezers please point me in the right direction?

I'm 100kg, and the slowest in the GPS team. I think the other guys use heavier balls than I do...