One piece of advice I would give you, is don't even think about trying to buy one off some random seller on ebay, as 95% are fake (yet everyone who has a signed shirt will be adamant that there's is the real deal).
Current squad is very difficult to obtain, and anything genuine would come at a premium. What is the persons age group? A legends shirt from a particular era might suit?
PM me, and I'll give you some more guidance, and some 100% genuine sellers who I know well, and who have arranged signing sessions with the players.