Hiya, light strikes avg 50 percent with a 13 lb mainspring, 20 percent with a 15 lb mainspring, and basically zero using 17 to 22 lb mainsprings. Try that first as your firing pin is prolly fine. What sourse are you using that tells you there is a pin that needs removing before your firing pin can be removed.
I'd imagine the cadet kit is downloadable via internet and don't think you will find such a pin. Those wooden q tips,that are to tight to leave cotton in the gun are good to run down the firing pin channel when cleaning and pins out. What happens to those two light strikes when you drop the hammer on them the second time?? So good luck, but if ya read the entire kadet post since 2002, you will find vast agreement the cadet needs 17lb mainspring to make .22 go bang. Be well.