Take it to a local gunsmith and ask for help.
best left to a gunsmith
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40-140 dollars depending on condition and a good bore.
Noble Arms made it for Montgomery Wards cross reference is Noble 60-66 shotgun
Westernfield (one word) was a name used by Montgomery Ward stores for shotguns sold by them. They were made by gun making companies, such as Savage, Winchester, Mossberg, etc. There were several different makes and models, and no one answer. Visit you local gun shop with the UNLOADED gun, and they should be able to show you.
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Blowback on a BB gun is a repeater. When you pull the trigger the gun fires and the top of the gun reciprocates (Blowsback) and auto load and cocks the next shot. If you have ever seen a modern forearm slide back an forth each time it is fired then you have seen Blowback.
This Westernfield is the same gun as a mossberg model 353. this may help find parts easier.
With the forearm removed from the barrel, hook the barrel onto the action at about a 45 degree angle. Once hooked, close the action. Replace the forearm to keep the barrel from coming off.
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