The Revelation 22 Model R100B caliber rifle was manufactured by Mossberg. The company Western Auto Supply is known to sell both these rifles as well as the cartridges for the rifle.
Please check the model number, and either repost or leave a message on my message board. Revelation was a store brand used by Western Auto Hardware stores for guns sold by them, but made by several makers. None of my refererences show a Model r100b. Sorry-
The price of a Revelation 22 Bolt Single Shot model R100B can vary based on factors such as condition, location, and whether it's being sold through a private sale or a retail outlet. Generally, you can expect prices to range from around $100 to $300. It's best to check local listings or online marketplaces for the most current pricing.
Revelation was a brand name used by Western Auto hardware stores for guns sold by them, but made by others. If yours is a single shot .22 bolt action rifle, whose safety goes on when you open the bolt, your rifle is a Mossberg Model 320B (Known as the Boy Scout model) The best source for Mossberg parts is Havlin Sales. Add dot com, and you have their address. Mr. and Mrs. Havlin are very nice people, and run the Mossberg Collectors Association. It would have helped to know what part you are looking for.