How to make a variable number with two positions

Dim $sequence = 00
; $Folder="C:\Program Files\PMAIL\MAIL\Docfxit\" ; Live
$Folder = "C:\Scratch\Scratch11\" ; Test
$File = InputBox("Find and replace", "Name and/or path of the file", "Hierarch.pm", "", 500, 100)
MsgBox(48, "Path\File", $Folder & $File)
$FileContent = FileRead($Folder & $File, FileGetSize($File))
$Find = InputBox("Find and replace", "What to find?", "FindThisText", "", 500, 100)
$Replace = InputBox("Find and replace", "What to write instead?", "ReplaceWithThisText", "", 500, 100)
$Confirm = MsgBox(65, "Find and replace", "You are about to change every instance of " & $Find & " by " & $Replace & " in the file " & $File & @LF & "Are you sure? ")
If $Confirm = 1 Then
    $sequence = $sequence + 1
    FileCopy($Folder & $File, $Folder & $File & $sequence)
    $FileContent = StringReplace($FileContent, $Find, $Replace)
    FileDelete($File)
    FileWrite($File, $FileContent)
EndIf