Ah, a brother in camp Tobin! I simply adore my plain grade, restocked and still nicely case colored 16 gauge. As others have posted for you, if you have one good firing pin and a machine shop that needs a little work, and money, you have two Tobin firing pins. They are really very simple to make.
But, brother, this usually isn't the problem in a Tobin that doesn't go bang. The cocking cams break on occasion, as do the rather complex, roller equipped springs, which double as cocking rods.
You may need more help than you know. But, if indeed it is a firing pin, that is a simple fix.
Enjoy. I sure enjoy mine.
Best,
Ted
