Ah, seems some people have forgotten about synthesis. I'm gonna be honest here, the Marine Space trick is a waste of time and Gala. I did some experimenting, and here's a much better solution.
Go into the convert shop, grab 99 Odd Souvenirs at 100 points per each, then head to the regular shop and synthesize them into Demon Kotodama. Costs 2500 gala per synthesis, just under a quarter million for the full 99.
Now go back to the convert shop, and turn those Demon Kotodama into points. They're worth 1200 points, giving you 118,800 points, and a net gain of 108,900 points. Then just repeat until you have as many points as you need.
Yeah, I've bought all the synth books available in the shop, but that was at the end of my first playthrough. I recently started a New Game+ on mega hard and I'm at Ch. 8, still can't buy any new synth books.
Tales of Graces F coming to North America. http://www.ataleoftworichards.com/