MsgBox FormatKeyWordArgs("$doto, $pudge", "doto:1", "pudge:3")

Public Function FormatKeyWordArgs(line As String, ParamArray kwargs()) As String
  If UBound(kwargs) <> 0 Then
    For Each key In kwargs
      words = Split(key, ":")
      line = Replace(line, "$" & words(0), words(1))
    Next
  Else
    On Error Resume Next
      words = Split(kwargs(0), ":")
    If Err.Number = 0 Then
      line = Replace(line, "$" & words(0), words(1))
    End If
  End If
  FormatKeyWordArgs = line
End Function