From Henry
You can find a firing pin for the ranger at Numerick Gun Parts Corporation.
You can find a replacement firing pin for a Stevens model 87D 22 cal rifle at a gun dealership. You can also find it by contacting the manufacturer.
If you look at the bolt face, a center fire rifle will have the firing pin located in the center of the bolt. A rimfire rifle will have the firing pin located on the outside edge of the bolt.
Try e-gunparts.com
Find a good gunsmith or machinist
e-gunparts.com
You can find a firing pin for a J.Stevens "Crack Shot" Model 26 by contacting Cardinal Promotions Inc. at email address: CardinalPromotions@mchsi.com
Ask a gunsmith for help
Any rifle that the firing pin strikes the bullet casing right in the center of the casing, causing it to discharge is called a "Center Fire Rifle." In contrast a "Rim Fire Rifle" the firing pin strikes the edge or rim of the bullet casing causing it to discharge.
google it.
http://www.wisnersinc.com/ They will have what you need!
Use a Marlin 57 firing pin. It's the same rifle, just re-branded for Sears.