This should get you started. Note that your concept might miss the last entry if it doesn't end with a # (which in your sample code appears to be a start point rather than a bracketing)
Code:
Sub Macro1()
Dim aRng As Range, sFound As String
Set aRng = ActiveDocument.Range
With aRng.Find
.ClearFormatting
.Replacement.ClearFormatting
.Text = "#*#"
.Forward = True
.Wrap = wdFindStop
.Format = False
.MatchWholeWord = False
.MatchWildcards = True
Do While .Execute = True
aRng.MoveStart Unit:=wdCharacter, Count:=1
aRng.MoveEnd Unit:=wdCharacter, Count:=-2
If Len(aRng.Text) > 32766 Then
Debug.Print "Oversize Block starting: " & aRng.Paragraphs(1).Range.Text
Else
'Do something with the found content
MsgBox aRng.Text
End If
aRng.Collapse Direction:=wdCollapseEnd
If aRng.End = ActiveDocument.Range.End Then
Exit Do
Else
aRng.End = ActiveDocument.Range.End
aRng.Select
End If
Loop
End With
End Sub