The Stevens 84C (Stevens was owned by Savage Arms, and the 84C is the same as the Savage 4C) was made with two different trigger guards during its production life. One was a simple curved steel trigger guard that was mounted to the surface of the stock. The other was a larger cast aluminum alloy trigger guard that fit into an "inlet" (cutout area) on the stock.
Both types of trigger guards are still available (in Jan 2012) from Numrich (aka Gun Parts Corp)
Try e-gunparts.com
updated answer: Stevens was owned by Savage Arms, and the Stevens model 87D is the same as the Savage model 6D (Stevens rifles were the lower cost siblings to the similar Savage models, usually with birch rather than walnut stocks, etc). The cast aluminum alloy trigger guard used by both versions of this rifle are still available (in Jan 2012) from Numrich (aka Gun Parts Corp) -- see: www.gunpartscorp.com/catalog/Products.aspx?catid=856 orignal answer: Try e-gunparts.com
I have a CNC Billet Aluminum tube fed trigger guard for a Winchester model 77. I have then polished or hard black anoidzed.
Cannot find an exact match- but if your trigger guard is black plastic- and especially if it has finger grooves in the tail of the guard- it was probably made by Mossberg. You can order replacement trigger guards from havlinsales.com There are 3 different trigger guards- check the photos to see if they match your rifle.
http://www.e-gunparts.com/productschem.asp?chrMasterModel=089Zz5100 This link is what your looking for.....copy and paste this link,there you will find your trigger guard for about $11.00 bucks and just about everything else for the 5100....including scematics for it....happy shopping.
Gun shops,garage sales,gun shows,E-bay etc.
There were a few that do not have a standard trigger, but use a THUMB trigger. Do a web IMAGE search for Winchester thumb trigger rifle, and you will find it.
The trigger guard is available from Numrich Gun Parts. There are two different types of trigger guards for the Savage 6d. The plastic guard that has a inletted area for the trigger guard in the stock and the simple bent metal trigger guard that just screws into the stock wood. Plastic trigger guard is product # 103530U $24.10 Metal guard is product # 10543OAL $11.50
http://www.forsterproducts.com/Pages/screws_trigger.htm
you can find parts for your Stevens at bob`s gun parts .com
check cabelas that's where i found a spare clip for my rifle
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.