Heavier springs for M&P compact (or lack thereof)

[Snowdog]

I recently purchased a few boxes of Underwood 125gr .357sig for use through my M&P40 compact with. 357sig Storm Lake barrel.

I haven't any doubts my M&P is up to punishment these rounds (haralded for producing non-watered-down .357sig velocities), but considering these could possibly scream from my compact at 1450 fps, I was hoping to increase the weight of the recoil spring by a few pounds.

I found Wolff does offer springs for the M&P, but not the compact. Do anyone know of others who might offer such springs? Wolff has been my go-to for all my spring needs and I'm having trouble finding what I need using Google.

Thanks in advance!