Greg Tannel at GreTan Rifles will bush the bolt down to 0.062 and remachine your firing pin for a better fit for under $80 shipped in less than a week's time.
You don't want a bigger pin you want a smaller pin as you get more support that way.
Put a 2x4 across a coffee can and a 250 pound person can stand on it.
Put the same 2x4 across a swimming pool and it is not supported and will bend or break.