Average $75-$100, depending on model or condition- and you did not tell us that.
See a gunsmith
Mossberg
the Winchester model 100 semi-auto rifle was made between 1961-1975.
Your Revelation 100 is a Mossberg 321. Numrich (gun parts corp) is sold out. You might check Havlin Sales- but the cost of a stock is likely to be half of the worth of the rifle- or more. Sorry-
your win model 100 semi-auto rifle was made in 1967.
your winchester model 100 semi-auto rifle was made by winchester in 1962.
With the serial number that you have supplied;your Winchester model 100 semi-auto rifle was made in the year 1963.
it is made in the 1700's
It may be a bolt action Mossberg model 321-320
If you know who made it, and they are still in business, probably.
The value of a Winchester Model 100 rifle made in 1967 is between $250 and $400. The actual value will depending largely on its actual condition.