This is a nice VG example (most are in this grade) of the semi-scarce 1900-O VAM22C1 Morgan dollar counterfeit associated with the Micro O family. The obverse die is the easily attributed example with the 2 bold die scratches between UM in UNUM. 
 
There are eight (8) or nine (9) documented counterfeit Morgan dollar varieties dated 1900-O from this family; the discrepency is whether VAM VNA-A is also associated with this family. Most of the 1900-O counterfeit varieties seem to be rare, or at least I have not been able to find them for sale, attributed or not by the owner/seller. When I have offered this variety for sale in the past, it seems to have sold quickly.