Heavier servo spring for Savage?

[Finnster]

The servo saver in the Sav seems pretty loose. I cranked down the spring preload on the SS nearly all the way, but it is still a bit sloppy with 300oz servos and 40 series tires. Anymore and I'm worried it won't have enough travel to move in a crash.

Is there a heavier duty spring out there for the Sav? This is supposed to be the HD one from HPI. I thought I saw an aftermarket one somewhere once, but now I can't find it. Perhaps a spring from a truggy SS would work?