You should definitely be able to do this if you are using either Windows and Office 2000 or XP, and you might be able to do it with Windows 98 and Office 97, but it would be more complicated.
If you have 2000 or XP, you first have to install Right to Left languages and then install one or more of the available Arabic language options in Windows and Office. Then, to display Arabic (or rather Indian) numbers in Word go to Tools/Options/Complex Languages tab and in the drop down list for numerals choose Hindi. All the numerals in the document will change to Hindi, and that should include the page numbers.
The bad news is that the numeral settings appear to be global, so all your numbers in all Word and Outlook documents will be either Hindi or Arabic, depending on what setting you have chosen.
If you need more information on how to install Arabic options in Windows or Office, let me know.