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Try e-gunparts.com
The Revelation Model 150 is a Marlin model 49: See; http://www.e-gunparts.com/productschem.asp?chrMasterModel=082Zz49+RIFLE MARLIN 49 RIFLE Barrel, .22 Cal., 22", Used, Stamped Revelation 150
go to e-gun part
Numrich Arms is a good source for gun parts.
Try e-gunparts.com
Revelation was a "store" brand used by Western Auto for guns sold by them, but made by others- usually Savage, Marlin and Mossberg. Find the model number from your rifle, and go to the website for gunpartscorp. Under the "company forum", on the left side, scroll down to "cross reference". Find the model number under Western Auto, and see what the original make and model was. Then contact that company, and request a manual.
Yes! Crosman made all the BB Guns/Rifles for Western Auto under the Revelation brand name. (Unfortunately you did not state the model number so I can't tell you exactly which Crosman model it relates to.) So here is a suggestion. Crosman has Most all their manuals online you will have to go through all of them to find your model. See the link below.
Take it to a gun smith.
Try gun shows.
Contact Colt, on line aucitons.
Gun shows, want ads, internet
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