The 38-year old, who spent 20 years at St James' Park, will be honoured with a clash between Toon stars and AC Milan greats in September.
Harper had not yet confirmed anything but posted on Twitter who some of the possibilities were.
Another testimonial meeting done & we're nearly there. Announcement next week hopefully. Shearer, Ginola etc v Baresi, Maldini etc. #legends— Stephen Harper (@steveharper37) July 3, 2013
Vieri,Shevchenko,Costacurta too confirmed. Just waiting for co-operation from all parties to confirm. Hopefully on Wed 11th Sep #all4charity— Stephen Harper (@steveharper37) July 3, 2013