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Numrich lists parts for both the hammergun version (aka: Stevens 215) and the hammerless (concealed hammer) version:
http://www.gunpartscorp.com/Manufact...side-33461.htm
The Savage/Stevens/Riverside doublegun dates from the 1st quarter of the 20th Century, and should be checked by a qualified double gunsmith (not some parts-changer) as being safe to shoot at all, before any repair to restore one to firing condition.
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