You can find a trigger guard for a Ranger 22LR model 103-13 at various online retailers that specialize in firearm parts, such as Brownells or MidwayUSA. Additionally, checking auction sites like GunBroker or eBay may yield results from individual sellers. Local gun shops or gunsmiths may also have the part or be able to order it for you. Lastly, consider reaching out to manufacturers or firearm forums for specific leads on parts availability.
Try gunbroker. Pull up Stevens 56.
I have a ranger model 101.13 that my father bought new in 1946
you will have to have a gunsmith check it to be sure.
The Ranger .22LR 103-13 that was sold through Sears was actually a Marlin model 81. It was made between 1937 and 1939.
Ten trillion dollars and 2 cents
Sears Ranger Mdl. 101.11A is a semi Auto, tube fed, rifle chambered for .22LR offered in the '30's. It was made for Sears by Savage/Stevens and is equivalent to their Mdls. 6A, 87A and 76A rifles. Values, these days, dependant on condition is in the $75 - $150 range. Very dependable rifles utilizing an interesting trigger disconnector system. When you fire the gun, the bolt remains to the rear until the trigger is released.
This is an operation best left to a S&W trained gun smith.
These guns were made for Sears by High Standard and are not very user friendly in disassembly. Make sure the gun is unloaded and remove the inner magazine tube. Remove the large slotted crossbolt at the rear of the receiver that goes through both wooden forearm extensions. You should be able to remove the trigger group downward. Do not lose the disconnector from the side of the trigger housing. Do not attempt to disassemble the trigger housing. If you attempt to remove the bolt, have a bandaid ready. http://www.histandard.info/manuals/sears/rfrifles/index.html
Inexpensive, probably made in the 60's.
A .22lr AS is a little more powerful. It's very similar to the .22 WMR
Best to take it to a good gunsmith.
22LR ammunition made to match specifications.