Paste into new workbook and save as depending on folders contents

[ScabbyDog]

I need a macro that copies all data on sheet1 in my open workbook and then opens a new workbook and pastes special as text into the new workbook. I then need it to save the new workbook as TigerX Csv file where x is a number. I need the number x to be determined by looking in a folder where there are already Tiger1 Tiger2 etc etc files and if the last number used was 2 then it would be saved as csv Tiger3. Any ideas??

[ScabbyDog]

Sub macro1()

Dim wb As Workbook
Dim FileOpen
Application.DisplayAlerts = False

Set wb = ThisWorkbook

Workbooks.Add

wb.Sheets("Sheet1").UsedRange.Copy Sheets("Sheet1").Range("A1")


ChDir "C:\Macro\Tests"
    ActiveWorkbook.SaveAs Filename:="C:\Macro\Tests\TigerX.csv", _
        FileFormat:=xlCSV, CreateBackup:=False

ActiveWorkbook.Close False

Application.DisplayAlerts = True

End Sub

I have the above which copies what I want, opens a new workbook and saves the new workbook as TigerX.csv but I need the X to change based on what is already in the folder. If the folder already has Tiger1.csv and Tiger2.csv I need this file to be saved as Tiger3.csv

[ScabbyDog]

Any way of writing a macro to check last used number in a specific folder?