Do you know how to book the sleeper train from Cairo to Aswan on

Do you know how to book the sleeper train from Cairo to Aswan on line? I find one website. www.sleepingtrains.com.
But it requires to pick up the ticket in Cairo at least 24 hours before departure.
Do you know any website to get the ticket on-line?
Thanks. I will be in Egypt before Chrismas (Back to USA on Chrismas Eve)
BTW, you miss Peru. That is the only one county I am interested in South America.Another country should be listed is Cambodia.
Have a good trip.