Did you try the web site for GunPartsCorp? I've purchased parts from them over the years. The older the firearm, the less chance they have the part. BUT... It's worth a try!!
There were two types of firing pin used on that model. Would need to see the bolt, but we have the pin. gunshop@nctv.com
Believe that is a Marlin 101. Contact Numrich at their website- gunpartscorp. They list that firing pin for $5 plus shipping,
Numrich Arms
Find a good gunsmith or machinist
gunpartscorp website has a cross reference to find the originial make and model, and usually his firing pins.
Use a Marlin 57 firing pin. It's the same rifle, just re-branded for Sears.
You can find a firing pin for the ranger at Numerick Gun Parts Corporation.
Try e-gunparts.com
Gunpartscorp.com
The 44DLM is the same as a Marlin 57M. The pin is available from Numrich gun parts Key # A57-28 Item # 378270 for around $18-$20. I have an old catalog so the price might have gone up.
Try e-gunparts.com
From Henry