Farm Friar Sand. He always gives lots of gold. I would guess an average of 5 to 7 grand per fight if you have more than one person fighting. The fact that you only have to defeat the Friar really speeds up the process. And his drops are really good too. I got all my companions trained to level 50 in just a couple of days of dedicated farming. With training points at level 50 costing 5100.00 each, this kind of return on your time is wonderful.
Thanks KI for providing a way for us to get past the super expensive cost of training. Friar Sand is a Hearrrty Haul for us poor pirates.