Lighter return springs, Fatar TP/8P?

I’d like to see if I can find lighter gauge return springs to soften the action of my Kurzweil Artis 7. It has the Fatar TP/8P 76 key keybed, which plays pretty “stiff” as-is. I’ve heard that others have had luck doing this and purchased the springs from Syntaur. Can you recommend the right springs and do you have any in stock?