Sub etalnew()
  Dim rngStory As Range
  For Each rngStory In ActiveDocument.StoryRanges
    
    Options.DefaultHighlightColorIndex = wdDarkYellow
    Selection.Find.Replacement.Highlight = True
    
    With rngStory.Find
      .Text = "<et al>"
      .Replacement.Text = "et^sal"
      .Replacement.Highlight = True
      .Wrap = wdFindContinue
      .MatchWildcards = True
      .Execute Replace:=wdReplaceAll
    End With
  Next rngStory
End Sub