I think Recode can do this:
Other way would be creating new column with some sort of column:
conversionAa = ["K" => "1e3", "M" => "1e6"];
If(Contains(conversionAa, Right(:Count, 1)),
Substitute(:Count, Right(:Count,1), conversionAa[Right(:Count, 1)])
);
My suggestion would be to use Recode and if you need the script you can get it from the Recode platform:
Names Default To Here(1);
dt = Data Table("Untitled");
dt << Begin Data Update;
col1 = dt << New Column(dt:Count);
col1 << Set Name("Count 2");
dt << Move Selected Columns({col1}, after(dt:Count));
dt << Recode Column(
dt:Count,
{Substitute(_rcNow, "K", "1e3"), Substitute(_rcNow, "M", "1e6")},
Target Column(col1)
);
dt << End Data Update;
-Jarmo