I think I have figured this out. Would the spring linked below work on the TP9SC? It looks like it would work on several gun models.I like the Racer style best as it lines up my trigger finger the way I like it. I have several others also that work just fine.
FPB spring= firing pin block spring. Glock and CZ replacements work fine. Very easy to do.
O-Ring mod. I'll have to send you pics and a link for how to do it. Not hard, just need some patience. Basically, an Eagle Claw D (oval shaped) ring from the fishing department. Need to see what size.
YouTube has videos on how to do these and they are ok if you have a few basic punches and hammer.
RP-FPBS Reduced Power Plunger Spring
CGW engineered music wire reduced power firing pin block plunger spring. This spring is very light, yet 100% reliable, virtually makes the feel of the FP block plunger go away. "Made in the USA"
cajungunworks.com