How much silver in a 1922 silver dollar?
The amount of pure silver in the 1922 Peace dollar is .77344oz, all US silver one dollar coins from 1840 to 1935 have this much silver in them.
It's not a silver eagle. Silver eagles are modern bullion coins sold to collectors. The dollar denomination is entirely artificial. A 1922 dollar coin is called a Peace dollar and was minted for use in daily commerce. At that time the price of silver was controlled and the coin contained a dollar's worth of silver.
A 1922 dollar with the word "Peace" on the back would be a Peace dollar rather than a Morgan dollar. "Morgan" refers to George T. Morgan, the artist who designed the silver dollars minted from 1878 to 1904 and in 1921. There's more information at the question "What is the value of a 1922 US silver dollar?"