Key 1 - The first possible spawn for the key to get Leroy out of the cage is on the wall to the left directly next to the cage door.
Key 2 - The second possible spawn is in the building to get to Leroy by jumping over the opening between the two buildings that have a workbench across from the bank. The key will be on the wall next to the whole to get to Leroy.
Key 3 - The third possible spawn is in the General Store next to the Bank and it will on hooks in the hall on the lower floor.
Key 4 - The fourth possible spawn is in the bank area on the wall of the vault.
Key 5 - The fifth possible spawn will be in the Salon where you buy Booze and it is in one of the rooms on the upper floor with a bed in it.
Key 6 - The final spawn is in the court house, hanging on the judges table.