Tevez looks set to return to South America this summer after Corinthians had a bid accepted by City for the striker.
Barry believes Aguero, Tevez's international team-mate, would be a great replacement for the City skipper, who he says still has the respect of the club's players despite wanting to leave.
"Aguero is a very exciting player from what I have seen on TV," Barry told reporters. "He is a class act. Names like that will excite fans and the players."
He added: "There has obviously been the odd chat about Carlos. He has made it clear he is ready to leave and the players will respect his decision.
"It is down to the club to decide what fee they want for Carlos. We would be sad to lose him because he is a class player who has worked really hard for the club.
"If you believe what you read, then yes, he has played his last game, but he has been great for Manchester City. He has helped the club win its first trophy and he has always given 100 per cent. We are grateful for that."